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Guidance on Design of Internet-based Process Control systems

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自动化学报 2005年第1期31卷 56-63页

作者： s.h.YANG L.YANG ComputerscienceDepartment LoughboroughUniversityLoughboroughLeicestershireLE113TUUK

Internet-based process control is becoming new generations of control systems, in which the Internet is used as a platform for global remote monitoring and control. The obvious benefit is to enable global collaboration between operators from geographically dispersed locations, data sharing and data provision for remote monitoring and control. however, connection to an open network and the use of universal technology present new problems that did not exist with the conventional design and construction of control systems, such as time delay and data loss in Internet transmission and security. This paper reviews the latest research results and presents design guidance of Internet based monitoring and control systems.

关键词：网络等待时间安全性用户界面设计互联网远程监控

Galvanic corrosion behavior of plain carbon steel-B_4C composite in 3.5% NaCl solution with electrochemical noise

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Journal of Central south University 2017年第1期24卷 1-8页

作者： s.h.Ettefagh Far A.Davoodi Young Researchers and Elites Club North Tehran BranchIslamic Azad University Department of Materials science and Engineering Faculty of EngineeringFerdowsi University of Mashhad(FUM)

The galvanic corrosion behavior of metal-matrix composite plain carbon steel/boron carbide （B4C） in 3.5% NaCl solution was studied. The composite was locally produced as a weld band on carbon steel by means of the gas tungsten arc welding process and using nickel as the wetting agent. samples from the weld band, heat-affected zone and parent metal region were extracted precisely and DC/AC electrochemical tests in combination with techniques such as scanning electron microcopy and energy dispersive spectrometry were conducted. The results of the electrochemical tests show that the corrosion resistance of the parent metal sample is higher than that of the welded composite and the hAZ samples. however, as the corrosion potential （Eco^r） of the parent metal is more positive than other two samples, this becomes the cathode in galvanic couples with two other samples. On the other hand, the weld composite sample is also cathodic due to its more positive Ecorr compared to hAZ sample. This means that the hAZ can be particularly at risk of preferential dissolution. The approach can be used in specific areas on plain carbon steel to locally increase hardness and resistance to abrasion and reduce manufacturing costs.

关键词： composites scanning electron microscopy potentiodynamic polarization electrochemical noise

Landau damping in a dipolar Bose–Fermi mixture in the Bose–Einstein condensation(BEC) limit

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Chinese Physics B 2016年第12期25卷 367-376页

作者： s M Moniri h Yavari E Darsheshdar Department of Physics University of Isfahan

By using a mean-field approximation which describes the coupled oscillations of condensate and noncondensate atoms in the collisionless regime, Landau damping in a dilute dipolar Bose-Fermi mixture in the BEC limit where Fermi superfluid is treated as tightly bounded molecules, is investigated. In the case of a uniform quasi-two-dimensional （2D） case, the results for the Landau damping due to the Bose-Fermi interaction are obtained at low and high temperatures. It is shown that at low temperatures, the Landau damping rate is exponentially suppressed. By increasing the strength of dipolar interaction, and the energy of boson quasiparticles, Landau damping is suppressed over a broader temperature range.

关键词： Landau damping mixtures of Bose and Fermi superfluids dipole-dipole interaction

study of hysteresis behavior in reactive sputtering of cylindrical magnetron plasma

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Chinese Physics B 2015年第12期24卷 392-399页

作者： h.Kakati s.M.Borah Jorhat Institute of science and Technology Department of Applied sciences Gauhati University

In order to make sufficient use of reactive cylindrical magnetron plasma for depositing compound thin films, it is necessary to characterize the hysteresis behavior of the discharge. Cylindrical magnetron plasmas with different targets namely titanium and aluminium are studied in an argon/oxygen and an argon/nitrogen gas environment respectively. The aluminium and titanium emission lines are observed at different flows of reactive gases. The emission intensity is found to decrease with the increase of the reactive gas flow rate. The hysteresis behavior of reactive cylindrical magnetron plasma is studied by determining the variation of discharge voltage with increasing and then reducing the flow rate of reactive gas,while keeping the discharge current constant at 100 m A. Distinct hysteresis is found to be formed for the aluminium target and reactive gas oxygen. For aluminium/nitrogen, titanium/oxygen and titanium/nitrogen, there is also an indication of the formation of hysteresis; however, the characteristics of variation from metallic to reactive mode are different in different cases. The hysteresis behaviors are different for aluminium and titanium targets with the oxygen and nitrogen reactive gases, signifying the difference in reactivity between them. The effects of the argon flow rate and magnetic field on the hysteresis are studied and explained.

关键词： cylindrical magnetron sputtering reactive mode hysteresis

Dirac oscillator in noncommutative space

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Chinese Physics C 2014年第6期38卷 23-29页

作者： h.hassanabadi s.s.hosseini s.Zarrinkamar Physics Department Shahrood University Shahrood Iran P. O. Box: ***-316 Shahrood Iran Department of Basic sciences Garmsar Branch Islamic Azad University Garmsar Iran

We study the Dirac oscillator problem in the presence of the Aharonov-Bohm effect with the harmonic potential in commutative and noncommutative spaces in s-= V and s =-V symmetry limits. We calculate exact energy levels and the corresponding eigenfunctions by the Nikiforov-Uvarov （NU） method and report the impact of the spin and the magnetic flux on the problem. helpful numerical data is included.

关键词： Dirac oscillator Aharonov-Bohm effect harmonic potential noncommutative space Nikiforov-Uvarov(NU) method

Design optimization of a slotless PM brushless motor with helical edge wound laminations for rim driven thrusters

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high Technology Letters 2010年第1期16卷 70-79页

作者： sharkh s M Lai s h school of Engineering sciences University of Southampton Highfield Southampton SO17 1BJ UK Applied Materials south East Asia Pte Ltd Changi Business Park Vista 486051 Singapore

This paper discusses the analysis and design of a very thin slotless permanent magnet （PM） brushless motor whose stator laminations are manufactured from a single strip of steel that is edge wound into a spiral （like a ＂slinky＂） and then fitted over the windings that are preformed on the outside surface of a non-conducting former. Analytical and finite element analysis （FEA） are used to determine the con- strained optimum dimensions of a motor used to drive a rim driven thruster in which the motor rotor is fit- ted onto the rim of the propeller and the stator is encapsulated in the thin Kort nozzle of the thruster. The paper describes the fabrication of a demonstrator motor and presents experimental results to validate the theoretical calculations. Experimental motor performance results are also reported and compared with those of a slotted motor that fits within the same active radial dimensions as the slotless motor. The slotless motor, which has longer active length and endwindings, and thicker magnets than the slotted motor, was found to be less efficient and more expensive （prototype cost） than the slotted machine.

关键词： slotless brushless permanent magnet (PM) motor edge-wound laminations rim driven thruster

Application of high silica zeolite ZsM-5 in a hybrid treatment process based on sequential adsorption and ozonation for VOCs elimination

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Journal of Environmental sciences 2016年第3期28卷 59-68页

作者： hicham Zaitan Marie hélène Manero héctor Valdés Laboratoire de Chirmie de la Matiere Condensee(LCMC) Faculte des Sciences et TechniquesUniversite Sidi Mohamed Ben AbdellahB.P.2202FesMaroc Universite de Toulouse INPTUPSLaboratoire de Genie Chimique4Allee Emile MonsoF-31030 ToulouseFrance CNRs Laboratoire de Genie ChimiqueF-31030 ToulouseFrance Laboratorio de Tecnologias Limpias(F.Ingenieria) Universidad Catolica de la Santisima ConcepcionAlonso de Ribera 2850ConcepcionChile

In this study,a hydrophobic synthetic zeolite,namely ZsM-5 is chosen as an adsorbent/catalyst for toluene *** results showed that toluene adsorption onto ZsM-5 was favourable,following a Langmuir adsorption isotherm ***-5 zeolite was regenerated using gaseous ozone at low *** toluene was oxidised,releasing mainly CO_2 and h_*** of oxidation by-products such as acetic acid and acetaldehyde were formed and remained adsorbed after the oxidativate regeneration with *** four successive cycles of adsorption/ozonation,the adsorption efficiency was not affected（92%-99%）.These results showed that volatile organic compound（VOC）removal by adsorption onto ZsM-5 zeolite followed by ozone regeneration could be used as a promising hybrid process for the control of VOC emissions in terms of efficiency.

关键词： Adsorption Ozone Toluene VOCs Zeolite

Creep Behavior and Microstructure Evolution of sand–Cast Mg–4Y–2.3Nd–1Gd–0.6Zr Alloy Crept at 523–573 K

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Journal of Materials science & Technology 2017年第1期33卷 79-89页

作者： Y.h.Kang h.Yan R.s.Chen The Group of Magnesium Alloys and Their Applications Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China University of the Chinese Academy of sciences Beijing 100049China

high temperature tensile-creep behavior of Mg-4Y-2.3Nd-IGd-O.6Zr （wt%, WE43（T6）） alloy at 523- 573 K was investigated. The creep stress exponent is equal to 4.6, suggesting the underlying dislocation creep mechanism. The activation energy is （199 _＋ 23） kJ/mol, which is higher than that for self- diffusion in Mg and is believed to be associated with precipitates coarsening or cross slip. The creep mechanism is further suggested to be dislocation climb at 523 K, while a cross slip at 573 K is possible. The metastable 13＇ and ~]1 phases in the WE43（T6） alloy were relatively thermal stable at 523 K and could be effective to hinder the dislocation climb, which contributed to its excellent creep resistance. however, at 573 K it readily transforms into equilibrium/3e phase and coarsens within two hours, thereby causing a decrease of creep resistance. In addition, precipitate free zones approximately normal to applied stress direction （directional PFZs） developed during the creep deformation, especially at 573 K. Those zones became preferential sites to nucleate, extend and connect microcracks and cavities, which lead to the intergranular creep fracture. Improving the thermal stability of precipitates or introducing thermally stable fine plate-shaped precipitates on the basal planes of Mg matrix could enhance the high temperature creep resistance.

关键词： WE43 alloy Creep PFZs Precipitate Fracture

Influence of Zn^(2+)or Cu^(2+) on Reduction and Recalcination Behavior of Fe_2TiO_5

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Journal of Materials science & Technology 2007年第5期23卷 697-702页

作者： M.Bahgat M.h.Khedr h.s.Abdelmaksoud CMRDI P.O.Box 87-HelwanCairoEgypt Chemistry Department Faculty of ScienceBenisuef UniversityEgypt

Fe2O3, TiO2, CuO and ZnO powders were mixed according to the formula of （1-x）TiO2 xCuO-Fe2O3 or （1-x）TiO2 xZnO-Fe2O3 （x=0, 0.2 0.4, 0.6, 0.8, 1）, and well ball-milled with h2O for 3 h to ensure homogeneity of the powdered solids, then fired at 1200℃ for 4 h. The fired samples were reduced at 500℃ with hydrogen gas. The reduced samples were subjected to recalcination at 500℃ in CO2 atmosphere. Both of fired, reduced and calcined samples were characterized by X-ray diffraction, vibrating sample magnetometry, reflected light microscopy and scanning electron microscopy. Different phases were formed after firing of Cu^＋2 or Zn^2＋ substituted Fe2TiO5. Magnetization （Bs） of the formed phases after firing are very low corresponding to diluted magnetic semiconductors （DMs） and increases with increasing the substituted cations （Cu^＋2 or Zn^2＋）. The reduction of the fired samples enhanced the Bs values whereas the reducibility increases with increasing the Cu^＋2 or Zn^2＋ content. samples show different tendency toward CO2 decomposition which is very important for environmental minimization for CO2.

关键词： Nanosized ferrite Titanate Reduction Magnetic properties Reduction-recalcin-ation CO2 decomposition