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Quantal studies of sodium 3p ← 3s photoabsorption spectra perturbed by ground lithium atoms

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Chinese Physics B 2019年第6期28卷 146-154页

作者： N Lamoudi F Talbi M T Bouazza M Bouledroua K Alioua Badji Mokhtar University B.P.12 AnnabaAlgeria laboratoire LESIMS laboratoire de physique des Rayonnements laboratoire LAMA Souk-Ahras University Souk-Ahras 41000Algeria

The pressure broadening in the far wings, where the sodium Na(3 p ← 3 s) resonance line is perturbed by ground lithium Li(2 s) atoms, has been theoretically analyzed. The NaLi potential–energy curves and the transition dipole moments are constructed by using a reliable ab initio data points to carry out the reduced-absorption coefficients k_r(ν, T). This quantum-mechanical investigation have demonstrated that the NaLi profile spectra show a satellite future in the red wing at wavelength λ = 685 nm in the temperature range 4000 K–1.8 × 10~4 K. The computation could also exhibit a second satellite, in the blue wing, near the wavelength λ = 574 nm beyond 6000 K and a third peak located at λ = 490 nm which begins to appear at 1.8 × 10~4 K.

关键词： pressure broadening absorption coefficient satellite structure radiative lifetime

Assessment of ship manoeuvrability by using a coupling between a nonlinear transient manoeuvring model and mathematical programming techniques

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Journal of Hydrodynamics 2013年第5期25卷 788-804页

作者： TRAN KHANH Toan OUAHSINE Abdellatif NACEUR Hakim EL WASSIFI Karima laboratoire Roberval Université de Technologie de Compiègne laboratoire LAMIH Université de Valenciennes Université Cadi Ayyad Faculté des Sciences et Techniques

In this paper, a numerical method based on a coupling between a mathematical model of nonlinear transient ship manoeuvring motion in the horizontal plane and mathematical Programming （MP） techniques is proposed. The aim of the proposed procedure is an efficient estimation of optimal ship hydrodynamic parameters in a dynamic model at the early design stage. The proposed procedure has been validated through turning circle and zigzag manoeuvres based on experimental data of sea trials of the 190 000- dwt oil tanker. Comparisons between experimental and computed data show a good agreement of overall tendency in manoeuvring traiectories.

关键词： ship manoeuvrability hydrodynamics coefficients nonlinear transient dynamics sensitivity analysis mathematical pro- gramming

Soil-atmosphere interaction in earth structures

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 35-49页

作者： Yujun Cui laboratoire Navier Ecole des Ponts ParisTechFrance

The soil-atmosphere interaction was investigated through laboratory testing,field monitoring and numerical *** the laboratory,the soil water evaporation mechanisms were studied using an environmental chamber equipped with a large number of sensors for controlling both the air parameters and soil *** sand and clay were *** case of sand,a dry layer could be formed during evaporation in the near surface zone where the suction corresponded to the residual volumetric water *** evaporative surface was situated at a depth where the soil temperature was the *** case of clay,soil cracking occurred,changing the evaporative surface from one-dimensional to three-dimensional *** suctionbased evaporation model was adapted to take these phenomena into account by adopting a function of dry layer evolution in the case of sand and by adopting a surface crack ratio and a retative humidity ratio in the case of *** the field,the volumetric water content,and the suction as well as the runoff were monitored for an embankment constructed with lime/cement treated *** appeared that using precipitation data only did not allow a correct description of the variations of volumetric water content and suction inside the soils,the consideration of water evaporation being *** was possible to use a correlation between precipiration and *** hydraulic conductivity was found to be a key parameter controlling the variations of volumetric water content and *** the numerical modelling,a fully coupled thermohydraulic model was developed,allowing analyzing the changes in temperature,volumetric water content and suction of soil,with the upper boundary conditions at the interface between soil and atmosphere determined using meteorological *** between simulations and measurements showed the performance of such numerical approach.

关键词： Environmental chamber Soil water evaporation Suction-based evaporation model Embankment Field monitoring Numerical modeling

Dynamical Study of a Constant Viscous Dark Energy Model in Classical and Loop Quantum Cosmology

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Chinese Physics Letters 2016年第5期33卷 144-148页

作者： Sara Benchikh Noureddine Mebarki Dalel Aberkane laboratoire de physique mathematique et Subatomique Mentouri University

Dynamical behaviors and stability properties of a flat space Friedmann-Robertson-Walker universe filled with pressureless dark matter and viscous dark energy are studied in the context of standard classical and loop quantum cosmology. Assuming that the dark energy has a constant bulk viscosity, it is found that the bulk viscosity effects influence only the quintessence model case leading to the existence of a viscous late time attractor solution of de- Sitter type, whereas the quantum geometry effects influence the phantom model case where the big rip singularity is removed. Moreover, our results of the Hubble parameter as a function of the redshift are in good agreement with the more recent data.

关键词： of on in Dynamical Study of a Constant Viscous Dark Energy Model in Classical and Loop Quantum Cosmology is that for been FRW

Theoretical prediction of structural,electronic and optical properties of quaternary alloy Zn_(1-x)Be_xS_ySe_(1-y)

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Chinese Physics B 2012年第3期21卷 321-327页

作者： Hacini K Meradji H Ghemid S El Haj Hassan F laboratoire LPR D'epartement de PhysiqueFaculté des SciencesUniversité de Annaba laboratoire de physique des matériaux Faculté des SciencesUniversité Libanaise

Within density functional theory based on the full potentiM-linearized augmented plane wave method, we carry out the first-principles calculation of the structural, electronic, and optical properties of the zinc blende quaternary alloy Zn1-xBexSySe1-y. The Perdew-Burke-Ernzerhof generaized gradient approximation based on the optimization of total energy and the Engel-Vosko generalized gradient approximation based on the optimization of the corresponding potential are used. Our investigation on the effect of the composition on lattice constants, bulk modulus, band gap, optical dielectric constant, and refractive index shows a non-linear dependence. The energy gap Eg（x, y） has been determined over the entire compositions x and y. In addition, the energy band gap of the technologically important quaternary alloy Znl-xBexSySe1-y in conditions of being lattice matched to ZnS substrate has been investigated. It is noteworthy that the present work is the first theoretical study of the quaternary alloy of interest.

关键词： density functional theory full potential-linearized augmented plane wave method qua-ternary alloy lattice-matched substrate

The Quantum Trihedron

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Chinese Physics Letters 2016年第11期33卷 28-30页

作者： A.Bendjoudi N.Mebarki laboratoire de physique mathematique et Subatomique Freres Mentouri University

The convex hull on three points in two-dimensional Euclidean space of three flat edges （trihedron） is studied. The Bohr-Sommerfeld quantization of the area of space is performed. It is shown that it reproduces exact... 详细信息

关键词： of in that is

X Y Z particles at BABAR

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Chinese Physics C 2010年第6期34卷 644-649页

作者： E.Prencipe LAPP-laboratoire de Annecy de physique de Particules

This paper intends to shortly summarize the recent results on Spectroscopy, published from the BABAR Collaboration. The BABAR experiment is a B-factory, at SLAC, where asymmetric energy beams of electron-positron are accelerated and collide at the energy in the center of mass of T（4S）. In 9 years of data taking, BABAR had collected 433 fb^-1 equivalent luminosity on-peak-data at the T（4S） energy, 30 fb^-1 data at the T（3S） energy, 15 fb^-1 data at the T（2S） energy, and a scan around T（4S） was done, collecting 25 pb^-1 every 5 MeV. Thanks to the high luminosity achieved, it is possible to perform high precision measurements, and spectroscopy studies. An update on the measurement of the state X（3872） will be given, as final result published by using the whole dataset available. Then, a new preliminary Y（4260） measurement is reported, and the study of the invariant mass J/ψπ^＋π^- in ISR events is shown, where no evidence of the state Y（4050） is highlighted. As conclusion, the results on the angular distribution analysis performed on the state Z（4430） are reported.

关键词： spectroscopy charmonium BABAR

Doppler Global Velocimeter-Development and Validation with Measurements in a Round Free Jet

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Journal of Thermal Science 2009年第1期18卷 74-84页

作者： X.Ottavy S.Goguey J.Berthiau I.Trébinjac laboratoire de Mécanique des Fluides et d’Acoustique(LMFA)

Doppler global velocimetry （DGV） has already been shown to be an interesting technique capable of measuring the three components of velocity in a plane. A 1-component DGV system is currently under development at the LMFA, using a stabilized continuous wave （CW） argon ion laser for ermssion, lne receiver Ieatures only one camera for both signal and reference images and incorporates a DEF1 system to adjust the incident laser light frequency and its transmission coefficient on the iodine cell absorption line. A description of the whole system is presented and a validation with measurements of axial velocities at several positions in a round free jet is proposed.

关键词： laser anemometry Doppler shift iodine vapor absorption line filter DEFI system image processing.

Properties of n-type SnO_2 semiconductor prepared by spray ultrasonic technique for photovoltaic applications

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Journal of Semiconductors 2015年第12期36卷 34-37页

作者： H.Bendjedidi A.Attaf H.Saidi M.S.Aida S.Semmari A.Bouhdjar Y.Benkhetta laboratoire de physique des Couches Minces et Applications Université de Biskra laboratoire des Couches minces et Interfaces Université Mentouri

Transparent conducting n-type SnO2 semiconductor films were fabricated by employing an inexpensive, simplified spray ultrasonic technique using an ultrasonic generator at deferent substrate temperatures （300, 350, 400, 450 and 500 ℃）. The structural studies reveal that the SnO2 films are polycrystalline at 350,400, 450, 500 ℃ with preferential orientation along the （200） and （101） planes, and amorphous at 300 ℃. The crystallite size of the films was found to be in the range of 20.9-72.2 nm. The optical transmittance in the visible range and the optical band gap are 80% and 3.9 eV respectively. The films thicknesses were varied between 466 and 1840 nm. The resistivity was found between 1.6 and 4 × 10^-2 Ω.cm. This simplified ultrasonic spray technique may be considered as a promising alternative to a conventional spray for the massive production of economic SnO2 films for solar cells, sensors and opto-electronic applications.

关键词： tin oxide thin films spray ultrasonic structural properties optical properties