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Entropy squeezing and atomic inversion in the k-photon Jaynes–Cummings model in the presence of the Stark shift and a kerr medium:A full nonlinear approach

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Chinese Physics B 2014年第7期23卷 417-428页

作者： H r Baghshahi M k Tavassoly A Behjat Atomic and Molecular Group Faculty of PhysicsYazd University The Laboratory of Quantum Information Processing Yazd University Department of Physics Faculty of ScienceVali-e-Asr University of Rafsanjan Photonics research Group Engineering Research CenterYazd University

The interaction between a two-level atom and a single-mode field in the k-photon Jaynes-Cummings model （JCM） in the presence of the Stark shift and a kerr medium is studied. All terms in the Hamiltonian, such as the single-mode field, its interaction with the atom, the contribution of the Stark shift and the kerr medium effects are considered to be f-deformed. In particular, the effect of the initial state of the radiation field on the dynamical evolution of some physical properties such as atomic inversion and entropy squeezing are investigated by considering different initial field states （coherent, squeezed and thermal states）.

关键词： Jaynes-Cummings model entropy squeezing atomic inversion intensity-dependent coupling

Structural, Optical, and Electrical Properties of Zn-Doped CdO Thin Films Fabricated by a Simplified Spray Pyrolysis Technique

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Acta Metallurgica Sinica(English Letters) 2015年第1期28卷 64-71页

作者： k.Usharani A. r.Balu PG and research Department of Physics AVVM Sri Pushpam College Poondi 613 503 Tamilnadu India PG and research Department of Physics AVVM Sri Pushpam College 757 MIG Colony New Housing UnitThanjavur 613 005 Tamilnadu India

Thin films of zinc-doped cadmium oxide with different Zn-doping levels（0, 2, 4, 6, and 8 at%） were deposited on glass substrates by employing an inexpensive, simplified spray technique using perfume atomizer at relatively low substrate temperature（375 °C） compared with the conventional spray method. The effect of Zn doping on the structural,morphological, optical, and electrical properties of the films was investigated. XrD patterns revealed that all the films are polycrystalline in nature having cubic crystal structure with a preferential orientation along the（1 1 1） plane irrespective of Zn-doping level. Zn-doping level causes a slight shift in the（1 1 1） diffraction peak toward higher angle. The crystallite size of the films was found to be in the range of 28–37 nm. The band gap value increases with Zn doping and reaches a maximum of 2.65 eV for the film coated with 6 at% Zn doping and for further higher doping concentration it *** studies indicate that Zn doping causes a reduction in the resistivity of the films and a minimum resistivity of15.69 X cm is observed for the film coated with 6 at% Zn.

关键词： Semiconductors Thin films Crystal structure Optical properties X-ray diffraction

Effect of Post Heat Treatment on Corrosion resistance of Phytic Acid Conversion Coated Magnesium

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Journal of Materials Science & Technology 2013年第2期29卷 180-186页

作者： r.k. Gupta k. Mensah-Darkwa D. kumar Engineering research Center for revolutionizing Metallic Biomaterials (ErC-rMB) Department of Mechanical Engineering North Carolina A&T State University 1601 East Market Street Greensboro NC 27411 USA

An environment friendly chemical conversion coating for magnesium was obtained by using a phytic acid solution. The effect of post-coating 1heat treatment on the microstructures and corrosion properties of phytic acid conversion coated magnesium was investigated. It was observed that the microstructure and corrosion resistive properties were improved for the heat treated samples. The corrosion current density for bare magnesium, phytic acid conversion coated magnesium, and post-coating heat treated magnesium was calculated to be 2.48 ×10^-5, 1.18×10^-6, and 9.27 × 10^7 A/cm^2, respectively. The lowest corrosion current density for the heat treated sample indicated its highest corrosion resistive effect for the magnesium. The maximum corrosion protective nature of the heat treated sample was further confirmed by the largest value of impedance in electrochemical impedance spectroscopy studies.

关键词： Magnesium Phytic acid Corrosion Impedance spectroscopy Scanning electron microscopy

Corrosion Protective Conversion Coatings on Magnesium Disks Using a Hydrothermal Technique

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Journal of Materials Science & Technology 2014年第1期30卷 47-53页

作者： r.k.Gupta k.Mensah-Darkwa D.kumar Department of Chemistry Pittsburg State University Engineering research Center for revolutionizing Metallic Biomaterials(ErC-rMB) Department of Mechanical EngineeringNorth Carolina A&T State University

A uniform, compact, and well adherent conversion coating of magnesium hydroxide has been formed on bioresorbable magnesium disks by means of a hydrothermal technique. Electrochemical results indicate that the coating brings about a significant reduction in magnesium corrosion in phosphate buffered saline （PBS） solution. It is also observed that corrosion resistance of the coating increases with an increase in treatment time, which in turn, increases the coating thickness. The protective behavior of magnesium hydroxide coating is attributed to its chemical inertness in PBS solution. The coatings are found to be free from pores that reduce the direct contact between corroding media and underlying magnesium.

关键词： Magnesium Polarization Electrochemical impedance spectroscopy (EIS) Scanning electron microscopy (SEM) Conversioncoating Corrosion

Mechanical and Corrosion Properties of Magnesiume-Hydroxyapatite (MgeHA) Composite Thin Films

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Journal of Materials Science & Technology 2013年第9期29卷 788-794页

作者： k.Mensah-Darkwa r.k.Gupta D.kumar Engineering research Center of revolutionizing Metallic Biomaterials Department of Mechanical Engineering North Carolina A & T State University Department of Chemistry Pittsburg State University

Magnesium(Mg)-hydroxyapatite(Ca10(PO4)6(OH)2,abbreviated as HA) composite films have been grown on Mg plates using a pulsed laser deposition *** property measurements and analysis have indicated that hardness and Young’s modulus of nMge(100e n)HA composite coatings increase with Mg content in the coatings and reach a maximum at a 70Mge 30HA composition.n and 100e n in the nMge(100e n)HA represent the relative number of laser pulses impinging on Mg and HA targets,*** current potentiodynamic polarization studies have shown that the corrosion of Mg plate(control) decreases with an increase in the HA ratio in the composite *** example,the corrosion current density of Mg plate reduces by w350 times after coating the Mg plate with 10Mge 90HA composite *** reduction in corrosion current density of Mg plates was also accompanied by a positive shift in the corrosion potential(w6%) due to this *** mechanism behind the reduction in corrosion behavior of Mg plates due to nMge(100e n) HA composite coatings has been understood by electrochemical impedance spectroscopy.

关键词： Magnesium Hydroxyapatite Scanning electron microscopy Pulsed laser deposition Corrosion Impedance spectroscopy

Development of an intelligent system based on ANFIS for predicting wheat grain yield on the basis of energy inputs

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Information Processing in Agriculture 2014年第1期1卷 14-22页

作者： Benyamin khoshnevisan Shahin rafiee mahmoud Omid Hossein Mousazadeh Department of Agricultural Machinery Engineering Faculty of Agricultural Engineering and TechnologyUniversity of TehranKarajIran

Energy is regarded as one of the most important elements in agricultural *** the last decades energy consumption in agriculture has increased,so finding the relationship between energy consumption and crop yields in agricultural production can help to achieve sustainable *** this study several adaptive neuro-fuzzy inference system(ANFIS)models were evaluated to predict wheat grain yield on the basis of energy ***,artificial neural networks(ANNs)were developed and the obtained results were compared with ANFIS *** the best ANFIS structure gained in this study,r,rMSE and MAPE were calculated as 0.976,0.046 and 0.4,*** developed ANN was a multilayer perceptron(MLP)with eleven neurons in the input layer,two hidden layers with 32 and 10 neurons and one neuron(wheat grain yield)in the output *** the best ANN model,r,rMSE and MAPE were computed as 0.92,0.9 and 0.1,*** results illustrated that ANFIS model can predict the yield more precisely than ANN.

关键词： Wheat yield Energy consumption Prediction ANFIS ANN

Tunnelling through weak and fragile rocks of Himalayas

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International Journal of Mining Science and Technology 2014年第6期24卷 783-790页

作者： Goel r.k. CSIr-Central Institute of Mining & Fuel research Regional CentreCBRI Campus Roorkee India

A considerable amount of tunnelling has been going on in India for various projects such as hydroelectric power, irrigation, roads and railways. Most of these projects are located in Himalayas, far away from the urban areas. Tunnelling through weak and jointed rock masses such as the one in the Himalayas is a challenging task for the planners, designers, engineers and geologists because of high overburden, thickly vegetated surface, weak, poor and fragile rocks and highly varying geology with the presence of numerous small and big shear zones, faults, etc. Due to these reasons, various tunnelling problems have been faced in the past and are still being encountered. Failures and the problems may be regarded as challenges and opportunities for generating new knowledge base and thereby increasing self-reliance in tunnelling. The experiences of Himalayan tunnelling through weak and fragile rocks covering varying and mixed geology, understanding on tunnelling in squeezing ground conditions and applicability of TBM in Himalayas are presented. It has also been highlighted that the probe holes planning, drilling and monitoring shall be followed seriously to reduce the geological surprises.

关键词： Varying geology Mixed geology Weak and fragile rocks Himalayan tunnelling Ground condition Squeezing

On Structure and Thermodynamics of Coherent Nanocrystals

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Journal of Materials Science & Technology 1995年第3期11卷 157-164页

作者： LUCk, r LU, k ACAD SINICA INST MET RESNATL KEY LAB RAPIDLY SOLIDIFIED NONEQUILIBRIUM ALSHENYANG 110015PEOPLES R CHINA ACAD SINICA INST MET RESINT CTR MAT PHYSSHENYANG 110015PEOPLES R CHINA MAX PLANCk INST MET rES INST WERKSTOFFWISSENSCHD-70174 STUTTGARTGERMANY

Several classifications for the nanocrystalline morphologies are introduced. It is: demonstrated that coherency and coherence strain are important physical quantities, which influence the stability, the morphology and... 详细信息

关键词： On Structure and Thermodynamics of Coherent Nanocrystals nm

Thermomechanical Control Process and Its Effect on Structure and Properties of High Strength Low Alloy Steels

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Journal of Iron and Steel research International 2011年第S1期18卷 511-520页

作者： Singh r k P Director Kalyani Centre for Technology & innovationSurvey No.15Ahead of Renuka Mata MandirKeshavnagarPuneIndia - 411036

Low carbon steels microalloyed with small amount of carbide and/or nitride forming elements such as Nb,Ti and V with Thermomechanical controlled processing (TMCP) can give fine grained ferrite structure with high strength and superior *** present study was aimed at identifying rolling parameters as well as microstructural characterization for accomplishing high yield strength and high charpy impact property at-60℃ by controlling hot rolling parameters and microstructure Grain size distribution was also monitored and related to mechanical properties of steel.

关键词： HSLA steel thermomechanical control processing grain refining precipitation recrystalization