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Plasma Science and Technology 2023年第3期25卷 87-94页

作者： N A ASHURBEkOV k O ImINOV k m RABADANOV G S SHAkHSINOV m Z ZAkARYAEVA m B kURBANGADZHIEVA Dagestan State University Department of Physics Harbin Institute of Technology Institute of Physics Dagestan Federal Research CenterRussian Academy of Sciences

This article presents the 2D simulation results of a nanosecond pulsed hollow cathode discharge obtained through a combination of fluid and kinetic *** spatio-temporal evolution of the electron energy distribution function(EEDF)of the plasma column and electrical characteristics of the nanosecond pulsed hollow cathode discharge at a gas pressure of 5 Torr are *** results show that the discharge development starts with the formation of an ionization front at the anode *** ionization front splits into two parts in the cathode cavity while propagating along its lateral *** ionization front formation leads to an increase in the fast isotropic EEDF component at its front,as well as in the anisotropic EEDF *** accelerated electrons enter the cathode cavity,which significantly contributes to the formation of the highenergy EEDF component and EEDF anisotropy.

关键词： pulsed nanosecond discharge electron energy distribution fuinction hollow cathode electron kinetics gas discharge

The dynamics of a nanosecond gas discharge development with an extended slot cathode in argon

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Plasma Science and Technology 2020年第12期22卷 78-88页

作者： N A ASHURBEkOV k O ImINOV G S SHAkHSINOV m Z ZAkARYAEVA k m RABADANOV Dagestan State University Faculty of PhysicsMakhachkala 367000Russia Institute of Physics DFRC of RASMakhachkala 367015Russia

The article presents the results of an experimental study and numerical modelling for the formation and development dynamics of a high-voltage transverse nanosecond discharge generated by a slot cathode in an argon medium at a pressure range of 1–10 Torr. Numerical modelling was carried out under similar experimental conditions for the processes of formation and propagation of ionisation waves, electron density distribution, excited atom and average electron energy in the discharge gap, including the cavity inside the cathode. At a pressure of p=1 Torr, a classical version of a high-voltage discharge is demonstrated to take place with no penetration of the plasma into the cathode cavity and no observed hollow cathode effect. An increase in gas pressure to 5 Torr leads to a penetration of plasma into the cathode cavity with the formation of a cathodic potential drop(CPD) region. Electrons emitted from the side surfaces of the cavity pass through the CPD region without collisions, oscillate inside the cathode cavity;the hollow cathode effect is fully manifested. At р=10 Torr, the modelling results qualitatively coincide with the results at р=5 Torr;in this case, however, hardly any accelerated electrons are observed in the gap between the electrodes, due to their energetic relaxation both inside the cathode cavity and when exiting from it. In both cases, the plasma structure formed at the exit of the cathode cavity involves a concentration of charged particles an order of magnitude higher than that in the rest of the gap, leading to a self-limiting discharge current effect. The results of the numerical modelling are in good agreement with experimental data.

关键词： nanosecond gas discharge numerical simulation argon excited atoms

Seasonal changes in Porteresia coarctata (Tateoka) beds along a subtropical coast

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Chinese Journal of Oceanology and Limnology 2013年第1期31卷 1-9页

作者： ABU HENA m k Department of Animal Science and Fishery Faculty of Agriculture and Food Sciences University Putra Malaysia Bintulu Sarawak Campus

Shoot density, standing crop （above- and below-ground biomass） and habitat of salt marsh grass Porteresia coarctata were investigated along the coast of Bakk.a.i estuary, Cox＇s Bazar, Bangladesh from January to December 2006. Shoot density of P. coarctata was influenced by season and was found to be higher （〉2 500 shoots/m2） in post-monsoon and minimal in monsoon season; plants were particularly active in vegetative propagation during pre-monsoon. Above-ground biomass was greater along the protected coast compared with the exposed one in this estuary. Below-ground biomass was higher （7.75-269.53 g DW/m2） than that above ground （2.20-114.75 g DW/m2）. Standing crops ofP. coarctata showed a negative relationship （R=-0.77; P〈0.05） with sedimentation rate, while seasonal activity influenced sedimentation. The recorded sedimentation rate was lower （6.09 mg/（cm2·d）） in pre-monsoon and highest （14.55 mg/（cm2·d）） in monsoon season. The mean value of pore water salinity was higher （34.25±65.05） during post-monsoon and lowest （18.0±3.71） in monsoon season. The soil was sandy clay in this P. coarctata bed; it consisted of 86% sand, 13% clay and 1% silt. Soil organic matter dropped during the monsoon season （0.78%-0.67%） and was highest （（2.17±1.42）%-（2.3±1.47）%） during post-monsoon, probably owing to accumulation of decomposed peat on the marsh surface. The mean pore water NH4-N concentration ranged from 2.444-1.65 to 3.33±1.82 μg/L, with a minimum air temperature of 22.09℃ in post-monsoon and a maximum of 31.16℃ in pre-monsoon. Variations of physico-chemical parameters in the soil, water, and climate governed biological parameters of P. coarctata in the Bakk.a.i estuary, and were comparable with estuarine environments elsewhere.

关键词： standing crop salt marsh Porteresia coarctata Bangladesh

A novel scheme of hybrid entanglement swapping and teleportation using cavity QED in the small and large detuning regimes and quasi-Bell state measurement method

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Chinese Physics B 2016年第10期25卷 45-51页

作者： R Pakniat m k Tavassoly m H Zandi Faculty of Physics Shahid Bahonar University of Kerman Faculty of Physics Atomic and Molecular Group Yazd University Research Group of Optics and Photonics Yazd University

We outline a scheme for entanglement swapping based on cavity QED as well as quasi-Bell state measurement(quasiBSm) methods. The atom–field interaction in the cavity QED method is performed in small and large detuning *** assume two atoms are initially entangled together and, distinctly two cavities are prepared in an entangled coherent–coherent state. In this scheme, we want to transform entanglement to the atom-field system. It is observed that, the fidelities of the swapped entangled state in the quasi-BSm method can be compatible with those obtained in the small and large detuning regimes in the cavity QED method(the condition of this compatibility will be discussed). In addition, in the large detuning regime, the swapped entangled state is obtained by detecting and quasi-BSm approaches. In the continuation,by making use of the atom–field entangled state obtained in both approaches in a large detuning regime, we show that the atomic as well as field states teleportation with complete fidelity can be achieved.

关键词： entanglement swapping quantum teleportation cavity QED quasi-Bell state measurement

Effect of anionic ordering on the electronic and optical properties of BaTaO2N：TB-mBJ density functional calculation

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Chinese Physics B 2017年第5期26卷 319-325页

作者： k Bettine O Sahnoun m Sahnoun m Driz LPQ3m University Mustapha Stambouli of Mascara Algeria University Djilali Liabes of Sidi Bel Abbes Algeria

This report presents a first-principles investigation of the structural, electronic, and optical properties of perovskite oxynitrides BaTaO2 N by means of density functional theory（DFT） calculations using the full-potential linearized augmented plane wave（FP-LAPW） method. Three possible structures（P4mm, I4/mmm, and Pmma） are considered according to the TaO4N2 octahedral configurations. The calculated structural parameters are found to be in good agreement with the previous theoretical and experimental results. moreover, the electronic band structure dispersion, total, and partial densities of electron states are investigated to explain the origin of bandgaps and the contribution of each orbital＇s species in the valence and the conduction bands. The calculated minimum bandgaps of the P4 mm, I4/mmm, and Pmma structures are 1.83 e V, 1.59 e V, and 1.49 e V, respectively. Furthermore, the optical properties represented by the dielectric functions calculated for BaTaO2 N show that the I4/mmm phase absorbs the light at a large window in both the visible and UV regions,whereas the other two structures（P4mm and Pmma） are more active in the UV region. Our investigations provide important information for the potential application of this material.

关键词： anionic perovskite octahedral bands dielectric augmented polar ordering struc orbital

Investigation of the inhomogeneous barrier height of an Au/Bi_4Ti_3O_(12)/n-Si structure through Gaussian distribution of barrier height

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Chinese Physics B 2012年第12期21卷 538-543页

作者： m.Gken m.Yildirim Department of Physics Faculty of Arts and SciencesDuzce University

A Au/Bi4Ti3O12/n-Si structure is fabricated in order to investigate its current voltage （IV） characteristics in a temperature range of 300 k-400 k. Obtained I-V data are evaluated by the thermionic emission （TE） theory. Zero-bias barrier height （Ф0） and ideality factor （n） calculated from I-V characteristics, are found to be temperature-dependent such that ФB0 increases with temperature increasing, whereas n decreases. The obtained temperature dependence of ФB0 and linearity in ФB0 versus the n plot, together with a lower barrier height and Richardson constant values obtained from the Richardson plot, indicate that the barrier height of the structure is inhomogeneous in nature. Therefore, I-V characteristics are explained on the basis of Caussian distribution of barrier height.

关键词： Bi4Ti3O12 I-V characterization temperature dependence Gaussian distribution

Stochastic seismic response of multi-layered soil with random layer heights

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 213-221页

作者： m.Badaoui m.k.Berrah A.mébarki Université Paris-Est Laboratoire Modélisation et Simulation Multi Echelle Ecole Nationale Polytechnique

This paper deals with the effect of layer height randomness on the seismic response of a layered soil. These parameters are assumed to be lognormal random variables. The analysis is carried out via monte Carlo simulations coupled with the stiffness matrix method. A parametric study is conducted to derive the stochastic behavior of the peak ground acceleration and its response spectrum,the transfer function and the amplification factors. The input soil characteristics correspond to a site in mexico City and the input seismic accelerations correspond to the Loma Prieta earthquake. It is found that the layer height heterogeneity causes a widening of the frequency content and a slight increase in the fundamental frequency of the soil profile,indicating that the resonance phenomenon is a concern for a large number of structures. Variation of the layer height randomness acts as a variation of the incident angle,i.e.,a decrease of the amplitude and a shift of the resonant frequencies.

关键词： random layer heights layered soil seismic acceleration lognormal distribution amplification factors mexico City

Teleportation of unknown states of a qubit and a single-mode field in strong coupling regime without Bell-state measurement

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Communications in Theoretical Physics 2023年第2期75卷 73-79页

作者： F Jahanbakhsh m k Tavassoly Optics and Laser Group Faculty of PhysicsYazd UniversityYazd 89195-741Iran

In this paper,we develop the teleportation scheme in[Zheng in Phys Rev A 69,064302,2004],in the sense that,we work in the strong atom-field coupling regime wherein the rotating wave approximation(RWA)is no longer *** achieve the purpose,a scheme consisting of a qubit interacting with a single-mode quantized field is described via the Rabi model(counter rotation terms are taken into account).Our first aim is to teleport an unknown atomic state of a qubit(which interacts with the quantized field in a cavity)to a second qubit(exists in another distant cavity field),beyond the RWA and without the Bell-state measurement *** the continuation,in a similar way,we teleport an unknown state of a single-mode field *** fact,it is shown that,in this regime,after applying some particular conditions,containing the interaction time of atom-field in the cavities,adjusting the involved frequencies,as well as the atom-field coupling in the model,if a proper measurement is performed on the state of the first qubit(the related field in the cavity),the unknown states of the qubit(field)can be teleported from the first qubit(cavity field)to the second qubit(cavity field),*** show that in both considered cases,the teleportation protocol is successfully performed with the maximum possible fidelity,1,and the acceptable success probability,0.25.

关键词： strong atom-field coupling Rabi model quantum teleportation success probability fidelity

The Potential of Wacapou (Vouacapoua americana) Extracts to Develop New Biobased Protective Solutions for Low-Durability Wood Species

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Journal of Renewable materials 2025年第1期13卷 79-100页

作者： Emma kieny kévin Candelier Louis milhe Yannick Estevez Cyrielle Sophie Romain Lehnebach Jérémie Damay Daniela Florez Emeline Houël marie-France Thévenon Julie Bossu CIRAD Ecologie de Forêts de Guyane(EcoFoG)AgroparisTechCNRSINRAEUniversitéde GuyaneKourou97379France CIRAD UPR BioWooEBMontpellierF-34398France BioWooEB Universitéde MontpellierCIRADMontpellierF-34398France CNRS Ecologie de Forêts de Guyane(EcoFoG)AgroparisTechCIRADINRAEUniversitéde GuyaneKourouGuyane Française97379France Sorbonne Université CNRSLaboratoire de Biodiversitéet Biotechnologies MicrobiennesLBBMObservatoire OcéanologiqueBanyuls-sur-Mer66650France

The valorization of Amazonian wood residues into active chemical compounds could be an eco-friendly,cost-effective and valuable way to develop wood preservative formulations to enhance the decay and termite resistance of low-durable wood ***(Vouacapoua americana.,Fabaceae)is a well-known Guianese wood spe-cies commonly used in local wood construction due to its outstanding natural durability,which results from the presence of a large panel of extractives *** addition,its industrial processing generates large amounts of *** residues were extracted by maceration using four different solvents(water/ethanol,ethyl acetate,hexane and dichloromethane/methanol),separately and *** yield of each extractive fraction was determined,and their chemical compositions were analyzed by Liquid Chromatography-mass Spectrometry(LC-mS).Ethyl acetate led to the highest extraction yield,and the active compounds were identiﬁed in the obtained extractive *** this sense,the fungicidal and termite-repellent properties of these extractives were then tested using a screening laboratory(with temperate and tropical microorganisms),according to the solution concentration(1%,2.5%,5%,8%and 10%).Finally,Virola michelii Heckel wood samples(low durable species)were impregnated with the 8%concentration *** impregnated wood samples were then exposed to a soil bed *** results highlighted that the nature of the solvent used during wood maceration affects the con-tent of the obtained extractive ***-Performance Liquid Chromatography–High-Resolution mass Spectrometry(UHPLC-HRmS)analyses showed the inﬂuence of extraction parameters on the nature of the extracted *** extracts(from ethyl acetate maceration)showed good anti-fungal and anti-termite ***,the concentration in extractives had an impact on the anti-termite activity level for Reti-culitermesﬂavipes and Cryptotermes *** based on W

关键词： Anti-fungal and anti-termite activities conferred durability extractives French Guiana impregnation guianese species wood by-products

Determination of stress intensity factors in half-plane containing several moving cracks

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Applied mathematics and mechanics(English Edition) 2013年第12期34卷 1535-1542页

作者： k.mALEk.a.EH FARD m.m.mONFARED k.NOROUZIPOUR Department of Structural Analysis and Simulations Space Research CenterKaraj-Tehran High Way Institute for Advanced Studies in Basic Sciences

The dynamic stress intensity factors in a half-plane weakened by several finite moving cracks are investigated by employing the Fourier complex transformation. Stress analysis is performed in a half-plane containing a single dislocation and without dislocation. An exact solution in a closed form to the stress fields and displacement is ob- tained. The Galilean transformation is used to transform between coordinates connected to the cracks. The stress components are of the Cauchy singular kind at the location of dislocation and the point of application of the the influence of crack length and crack running force. Numerical examples demonstrate velocity on the stress intensity factor.

关键词： moving crack stress intensity factor half-plane Cauchy singularity