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Organic light Emitting Diodes with lithium Contained Alq3 as Electron Inj.ction layer

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Chemical Research in Chinese Universities 2002年第2期18卷 121-123页

作者： Zugang liu j.l.Pinto Department of Materials University of OxfordParks RoadOxford OX13PFUK Departamento de Física Universidade de Aveiro3810194 AveiroPortuga

lNovel lithium doped tris 8 hydroxylquinoline aluminium(Alq3:li) layer is deposited between emission layer and electron inj.ction aluminium electrode as an electron inj.ction assistant layer in different organic light emitting diodes(OlED) to lower the electron inj.ction barrier. In these devices, Alq3 is used as emission layer, and a bilayer film of N,N bis (1 naphhyl) N,N diphenyl 1,1 biphenyle 4,4' diamine(NPB) and 4,4,4' tris(3 methyl phenylphenylamino) triphenylamine( m MTDATA) used as hole transport layer(HTl). The electroluminescent performance of devices with different thicknesses of Alq3∶li shows that the insertion of the lithium doped Alq3 layer can reduce the turn on voltage by at least 2 volts, and the stability of devices with this lithium doped Alq3 layer is improved too. It can also change the efficiency of devices. Compared with an ultra thin lithium fluoride(liF) layer, Alq3∶li sheet gives similar effects but higher efficiency and can be much thicker and hence it is easier to control the deposition.

关键词： Organic light emitting diodes lithium layer Alq3 EI

Design and Robust Performance Evaluation of a Fractional Order PID Controller Applied to a DC Motor

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IEEE/CAA j.urnal of Automatica Sinica 2017年第2期4卷 304-314页

作者： j.Viola l.Angel j.M.Sebastian Universidad Pontificia Bolivariana Universidad Politecnica de Madrid Centre for Automation and Robotics (CAR) UPM-CSIC

This paper proposes a methodology for the quantitative robustness evaluation of PID controllers employed in a DC motor. The robustness analysis is performed employing a 2~3 factorial experimental design for a fractional order proportional integral and derivative controller(FOPID), integer order proportional integral and derivative controller(IOPID)and the Skogestad internal model control controller(SIMC). The factors assumed in experiment are the presence of random noise,external disturbances in the system input and variable load. As output variables, the experimental design employs the system step response and the controller action. Practical implementation of FOPID and IOPID controllers uses the MATlAB stateflow toolbox and a NI data acquisition system. Results of the robustness analysis show that the FOPID controller has a better performance and robust stability against the experiment factors.

关键词： Factorial experimental design fractional-order PID controller robustness analysis SIMC PID controller

STRUCTURE, MAGNETISM AND MAGNETORESISTANCE OF ANNEAlED Co/Cu DISCONTINUOUS MUlTIlAYERS

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Acta Metallurgica Sinica(English letters) 1997年第6期10卷 465-473页

作者： Yan, S.S. lou, j.X. Zhang, l. Zhang, R.Z. Zhang, Y.M. liu, Y.H. Mei, l.M. Huang, j. Shandong Univ Jinan China

Co/Cu discontinuous multilayers were prepared by rf-sputtering method under high sputtering power and then annealed at various temperatures in a high vacuum. The structural, magnetic and transport properties were strongly influenced by the annealing temperature. The annealed samples obviously became discontinuous multilayers. A maximum magnetoresistance ratio of 5.6% was obtained under a relatively low saturation field of about 400 (10/4π) A/m at the optimum annealing temperature of 450°C. When the annealing temperature was increased, the resistivity decreased, and the coercive force and the saturation field increased. The magnetoresistance ratio also depended on the thickness of Co and Cu layers. The magnetic and transport properties were explained on the basis of the discontinuous multilayered structure.

关键词： Copper Magnetic properties Multilayers Sputtering Transport properties

Diameter-dependent in vitro performance of biodegradable pure zinc wires for suture application

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j.urnal of Materials Science & Technology 2019年第8期35卷 1662-1670页

作者： H. Guo R.H. Cao Y.F. Zheng j. Bai F. Xue C.l. Chu State Key laboratory for Turbulence and Complex System and Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China School of Materials Science and Engineering Southeast University Nanjing 211189 China Key laboratory for Advanced Metallic Materials Southeast University Nanjing 211189 China

In this study, biodegradable pure zinc wires with 3.0 mm and 0.3 mm in diameter were prepared via hot-extrusion and subsequent cold-drawing process respectively. The microstructure, mechanical performance, corrosion behavior, in vitro cytocompatibility and antibacterial effect were comparatively *** cold-drawing, the mechanical property, especially the elongation of the ф0.3 mm pure Zn wire was improved significantly compared with the ф3.0 mm pure Zn wire. The in vitro corrosion study including immersion and electrochemical test showed acceptable corrosion resistance of these two materials in Hank's solution. The in vitro Human Umbilical Vein Endothelial Cells(HUVECs) viability assay showed obviously different results, in which the ф0.3 mm pure Zn wire demonstrated favorable cytocompatibility, while the ф3.0 mm wire exhibited severe cytotoxic effect with 100% extract concentration. Both of them exhibited partly antibacterial effect on S. aureus. These results demonstrated the feasibility of the prepared 0.3 mm pure Zn wire as the potential suture material with good absorbability.

关键词： Pure zinc Wire Biodegradable metal Suture

Frictionally excited thermoelastic dynamic instability of functionally graded materials

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Acta Mechanica Sinica 2019年第1期35卷 99-111,I0004页

作者： j.liu l.l.Ke Y.S.Wang College of Engineering Huazhong Agricultural UniversityWuhan 430070China Institute of Engineering Mechanics Beijing JiaotongUniversity Beijing 100044China

The perturbation method is applied to investigate the frictionally excited thermoelastic dynamic instability (TEDI) of a functionally graded material (FGM) coating in half-plane sliding against a homogeneous half-plane. We assume that the thermoelastic properties of the FGM vary exponentially with thickness. We also examine the effects of the gradient index, sliding speed, and friction coefficient on the TEDI for various material combinations. The transverse normal stress for two different coating structures is calculated. Furthermore, the frictional sliding stability of two different coating structures is analyzed. The obtained results show that use of FGM coatings can improve the TEDI of this sliding system and reduce the possibility of interfacial failure by controlling the interfacial tensile stress.

关键词： Thermoelastic dynamic instability Frictional heat Functionally graded materials Stress analysis

Numerical study of the circular opening effect on mechanical behaviour of rock under confinement

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j.urnal of Rock Mechanics and Geotechnical Engineering 2019年第6期11卷 1201-1210页

作者： Y.l.Gui j.l.Shang j.j.Ma Z.Y.Zhao school of engineering newcastle universitynewcastle upon tynene17ruunited kingdom school of civil and environmental engineering nanyang technological university639798singapore school of civil engineering sun yat-sen universityguangzhou510275china

Opening holes in rock including their size and distribution can affect the performance of rock-related structures.A good understanding on this will contribute to,for example,rock cavern design,and construction,tunnelling,and mining *** improve the understanding,a comprehensive investigation of the opening hole effect on the rock mechanical behaviour under biaxial loading condition is carried out by virtue of a hybrid continuum-discrete element *** specimens with both single hole and multi-hole of various radii are investigated and compared with the cases subj.cted to uniaxial *** is demonstrated that the confining pressure can increase both the stiffness and strength due to delaying the crack initiation and *** increase due to the confining pressure is more evident for the compressive *** single hole specimens with 0.75 mm radius hole,the increase ratio of the compressive strength is a linear increasing function with width and the increase ratio ranges from 2.15 for the specimen with 3.5 mm width to 2.45 for 10 mm *** the single hole specimen with 10 mm width,the increase ratio starts at 2.13 for the specimen with 0.75 mm radius hole,ascending to the peak of 2.37 for the specimen with 1 mm radius hole,followed by a decline to 2.2 for the specimen with 1.25 mm radius ***,for the multi-hole specimens,the increase ratio varies from 1.66 to *** addition,to verify the influence of confining pressure magnitude on the performance of the rock specimens,totalling 10 confining pressure levels are applied and *** simulation results show that even though there are opening holes in the specimens,the simulated compressive strength generally follows the generalised Hoek-Brown model.

关键词： Rock with opening Simulation Biaxial loading Strength Stiffness

DSC analyses of static and dynamic precipitation of an Al–Mg–Si–Cu aluminum alloy

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Progress in Natural Science:Materials International 2015年第2期25卷 153-158页

作者： Manping liu Zhenj.e Wu Rui Yang j.angtao Wei Yingda Yu P?l C. Skaret Hans j. Roven School of Materials Science and Engineering Jiangsu Province Key Laboratory of Materials Tribology Jiangsu University Department of Materials Science and Engineering Norwegian University of Science and Technology (NTNU)

In the present investigation, both static and dynamic precipitations of an Al–Mg–Si–Cu aluminum alloy after solid-solution treatment(SST)were comparatively analyzed using differential scanning calorimetry(DSC). Dynamic aging was performed in the SST alloy through equal channel angular pressing(ECAP) at different temperatures of room temperature, 110, 170, 191 and 300 1C. For comparison, static artificial aging was conducted in the SST alloy at 191 1C with two aging times of 4 and 10 h. The DSC analyses reveal that the dynamic precipitation has occurred in the ECAPed samples, while the activation energies associated with the strengthening precipitates in the dynamic samples are considerably higher than the energies in the SST and static aged samples. The higher activation energies are probably attributed to the smaller grains and higher dislocation density developed after ECAP. The results in the present investigation allow the prediction of the type of the dynamic precipitates to influence the strength of the ultrafine grained alloy during ECAP at various temperatures.

关键词： Differential scanning calorimetry Al–Mg–Si–Cu aluminum alloy Dynamic aging Precipitation behaviors Equal channel angular pressing Severe plastic deformation

EFFECT OF STRUCTURAl PARAMETERS ON THE THERMAl STRESS OF A NiFe_(2)O_(4)-BASED CERMET INERT ANODE IN AlUMINUM ElECTROlYSIS

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Acta Metallurgica Sinica(English letters) 2007年第2期20卷 139-147页

作者： j. li Z.G. Wang Y.Q. lai Y.Y. Wu S.l. Ye School of Metallurgy Science and Engineering Central South University Changsha 410083 China

Inert anode has been a hot issue in the aluminum industry for many decades. With the help of FEA （finite element analysis） software ANSYS, a model was developed to simulate the thermal stress distribution working condition of an inert anode. To reduce its thermal stress, the effect of some parameters on the thermal stress distribution was investigated, including the anode height, the anode radius, the hole depth, the hole radius, and the radius of inner chamfer and outer chamfer. The results showed that in the actual working condition of an inert anode, there existed a large axial tensile stress near the tangent interface between the anode and bath, which was the maj.r cause of anode breaking. Increasing the anode height and reducing the hole depth properly seemed to be beneficial for the stress distribution. With the increase of anode radius, the stress distribution became better first and then deteriorated, the reasonable value was between 0.045 to 0.06m. The hole radius had a significant effect on the stress and a smaller radius would reduce the thermal stress. The effect of the radius of the inner chamfer and the outer chamfer was less than other parameters.

关键词： inert anode thermal stress structural parameter aluminum electrolysis

Molecular Frame Photoemission： Probe of the Photoionization Dynamics for Molecules in the Gas Phase

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Chinese j.urnal of Chemical Physics 2009年第2期22卷 178-186页

作者： D. Dowek Y. j. Picard P. Billaud C. Elkharrat j. C. Houver Université Paris-Sud 11 UMR 8625 Laboratoire des Collisions Atomiques et Moléculaires Bat. 351 Université Paris-Sud 91405 Orsay France CNRS UMR 8625 Laboratoire des Collisions Atomiques et Moléculaires Bat. 351 Université Paris-5ud 91405 Orsay France

Molecular frame photoemission is a very sensitive probe of the photoionization （PI） dynamics of molecules. This paper reports a comparative study of non-resonant and resonant photoionization of D2 induced by VUV circularly polarized synchrotron radiation at SOlEIl at the level of the molecular frame photoelectron angular distributions （MFPADs）. We use the vector correlation method which combines imaging and time-of-flight resolved electron-ion coincidence techniques, and a generalized formalism for the expression of the Ⅰ（χ, θe, Фe） MFPADs, where χ is the orientation of the molecular axis with respect to the light quantization axis and （θe, Фe） the electron emission direction in the molecular frame. Selected MFPADs for a molecule aligned parallel or perpendicular to linearly polarized light, or perpendicular to the propagation axis of circularly polarized light, are presented for dissociative photoionization （DPI） of D2 at two photon excitation energies, hv=19 eV, where direct PI is the only channel opened, and hv=32.5 eV, i.e. in the region involving resonant excitation of Q1 and Q2 doubly excited state series. We discuss in particular the properties of the circular dichroism characterizing photoemission in the molecular frame for direct and resonant PI. In the latter case, a remarkable behavior is observed which may be attributed to the interference occurring between undistinguishable autoionization decay channels.

关键词： Dissociative photoionization Molecular frame photoemission Circular dichroism in photoemission Autoionization dynamics Synchrotron radiation Vector correlation