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Spin and Orbital Magnetisms of NiFe Compound:density Functional Theory Study and Monte Carlo Simulation

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Chinese Physics Letters 2018年第3期35卷 58-61页

作者： R.Masrour A.Jabar E.K.Hlil M.Hamedoun A.Benyoussef A.Hourmatallah K.Bouslykhane A.Rezzouk N.Benzakour Laboratory of Materials ProcessesEnvironment and QualityCady Ayyed UniversityNational School of Applied SciencesSail 63 46000Morocco Institut Neel CNRS et Universite Grenoble AlpesBP 166F-38042 Grenoble Cedex 9France Institute of Nanomaterials and Nanotechnologies MAScIRRabatMorocco Hassan II Academy of Science and Technology RabatMorocco Equipe de Physique du Solide Laboratoire LIPIEcole Normale SuperieureBP 5206BensoudaFesMorocco laboratoire de Physique du Solide Universite Sidi Mohammed Ben AbdellahFaculte des Sciences Dhar MahrazBP 1796FesMorocco

The self-consistent ab initio calculations based on the density functional theory approach using the full potential linear augmented plane wave method are performed to investigate both the electronic and magnetic properties of the NiFe compound. Polarized spin within the framework of the ferromagnetic state between magnetic ions is considered. Also, magnetic moments considered to lie along （001） axes are computed. The Monte Carlo simulation is used to study the magnetic properties of NiFe. The transition temperature To, hysteresis loop, coercive field and remanent magnetization of the NiFe compound are obtained using the Monte Carlo simulation.

关键词： Fe Spin and Orbital Magnetisms of Ni Fe Compound Ni

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foF2 Diurnal Variability at African Equatorial Stations:Dip Equator Secular Displacement Effect

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International Journal of Geosciences 2013年第8期4卷 1145-1150页

作者： Doua A.Gnabahou Frederic Ouattara Emmanuel Nanema Francois Zougmore laboratoire d’Enseignement et de Recherche en Sciences Experimentales et Mathematiques Ecole Normale Superieure de l’Universite de KoudougouKoudougouBurkina Faso laboratoire des Materiaux et Environnement Universite de OuagadougouOuagadougouBurkina Faso Institut de Recherches en Sciences Appliquées et Technologies/Centre National de la Recherche Scientifique et Technologique OuagadougouBurkina Faso

The paper goal is to analyze the variability of foF2 at African equatorial stations and the effect of dip angle on this variability. The gap between the dip angle of Dakar and Ouagadougou is superior to that between Djibouti and Ouagadougou. The trend of the dip angle at Ouagadougou and Dakar decreases while that of Djibouti increases. The relative position of the station with respect to the equator and the trend sign explains the difference observed in foF2 variability at Dakar station and at the two other stations. At Djibouti and Ouagadougou, foF2 exhibits noon bite out profile during all solar cycle phases while at Dakar observed profile is dome or plateau during the maximum and the predominance afternoon peak for the other solar cycle phases.

关键词： Dip Angle foF2 Diurnal Variability Solar Cycle Phase

Giant atoms interacting with radiation

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激光 1980年第Z1期 31-31页

作者： Serge Haroche laboratoire de Physique de 1’ecole normale superieure

Rydberg atoms are atoms in which the valence electron has been excited to a verybig orbital corresponding to a large value of the principal quantum number *** pre-paration and study of these“giant atoms”have been made possible by the developmentof tunable lasers which allow us to selectively excite from a ground or a metastable state,in one-or multiple-step,any Rydberg level of given n(10(?)n(?)100) and l angularquantum *** properties of these species are quite different from those of or-dinary ground-state or moderately excited atomic systems,which makes the physics of

关键词： very In Giant atoms interacting with radiation

Assessment of Radioactivity in Borehole Waters of the North Riviera Sodeci Catchment Field in Abidjan, Côte d’Ivoire

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World Journal of Nuclear Science and Technology 2022年第1期12卷 55-68页

作者： Epi Zita Tatiana Kocola Achi Bogbé Douo Louis Huberson Gogon Koudou Djagouri Marie Chantal Kouassi Goffri laboratoire des Sciences de la Matière Environnement et de l’Energie Solaire (LASMES) Université Felix Houphouet Boigny Abidjan C&#244 te d’Ivoire Autorité de Radioprotection de Sureté et de sécurité Nucléaire Abidjan C&#244 te d’Ivoire ecole normale superieure d’Abidjan Abidjan C&#244 te d’Ivoire

The radioactive isotopes of the decay series of uranium-238 (238U), thorium-232 (232Th) and potassium-40 (40K) occur naturally in varying amounts in groundwater. They are the subject of many measures, mainly because of the risk they represent from a public health point of view. The purpose of this study is to measure the radioisotope content of borehole waters from the north riviera (NR) catchment field of the Ivorian drinking water distribution company (SOdeCI). These measurements will make it possible to assess the absolute levels of radioisotopes in the water from SOdeCI’s boreholes used directly for drinking or swimming, and possibly the associated risk from a public health point of view. To achieve this, a sampling campaign from the seven functional boreholes and the control or treatment tower took place in July 2018 at the NR well field. The analysis of radionuclides by gamma spectrometry was carried out in the laboratory of the Radiation Protection Institute (RPI) of the Ghana Atomic Energy Commission (GAEC). The naturally occurring radionuclides identified during the borehole water samples analysis are 238U, 232Th, and 40K. The results reveal that the specific activities of uranium vary from 0.45 ± 0.18 Bq/L to 0.55 ± 0.17 Bq/L with an average of 0.49 ± 0.15 Bq/L. Those of thorium vary from 0.66 ± 0.14 Bq/L to 0.78 ± 0.18 Bq/L with an average of 0.72 ± 0.16 Bq/L and potassium of 4.14 ± 0.53 Bq/L at 5.87 ± 0.60 Bq/L with an average of 5.32 ± 0.58 Bq/L.

关键词： North Rivera (NR) Catchment Field Drilling Water Natural Radionuclides Uranium Thorium Potassium

Late Neogene evolution of the East Asian monsoon revealed by terrestrial mollusk record in Western Chinese Loess Plateau:From winter to summer dominated sub-regime

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Late Neogene evolution of the East Asian monsoon revealed by...

Cavity-based photoconductive sources for real-time terahertz imaging

中国科学院地质与地球物理研究所2008学术年会

作者： denis-Didier Rousseau laboratoire de Meteorologie Dynamique UMR INSU-CNRS 8539 & CERES-ERTIEcole Normale Superieure24 rue de Lhomond75231 Paris cedex 05France Lamont-Doherty Earth Observatory of Columbia University PalisadesNew York 10964USA

More and more evidence indicates that the onset of the East Asian(EA) monsoon can be traced back to the Oligocene-Miocene boundary(at about 23 Ma).However,the process of its evolution is still less well-known until *** we investigate its late Neogene evolution by analyzing a terrestrial mollusk sequence,from the Chinese Loess Plateau(CLP),covering the period between 7.1 and 3.5 *** the modern ecological requirements of these organisms,we were able to define two groups of cold-aridiphilous(CA) and thermo-humidiphilous(TH) species,representing the EA winter and summer monsoon variations, respectively,as previously defined in the Quaternary glacial-interglacial *** in these two groups indicate two different monsoon dominated periods during 7.1-3.5 ***,between 7.1 and 5.5 Ma, the EA winter monsoon,with a 100-kyr periodicity,was ***,between 5.1 and 4 Ma,the EA summer monsoon dominated,with a 41-kyr ***,our mollusk record yields valuable evidence for a late Miocene-Pliocene transition of about 400 kyr from winter monsoon dominated towards summer monsoon dominated,associated with a periodicity transition from weak 100 kyr to 41 *** strengthened winter monsoon interval,with a 100-kyr periodicity,is coeval with orbital-scale global icevolume changes,in conjunction with the uplift of the Tibetan Plateau which probably reinforced the winter monsoon ***,closures of the Panama and Indonesian seaways,associated with changes in obliquity between 5.1 and 4 Ma,are probably major forcing factors for the observed dominant summer monsoon with 41-kyr frequency,favoring heat and moisture transports between low and high latitudes to allow TH mollusks to grow and develop in the CLP.

关键词： East Asian monsoon land snails loess late Miocene Pliocene ice sheets obliquity eccentricity tectonic changes

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Photonics Research 2020年第6期8卷 858-863页

作者： J.HAWECKER V.PISTORE A.MINASYAN K.MAUSSANG J.PALOMO I.SAGNES J.-M.MANCEAU R.COLOMBELLI J.TIGNON J.MANGENEY AND S.S.DHILLON laboratoire de Physique de I'ecole normale superieure ENSUniversite PSLCNRSSorbonne UniversiteUniversite de ParisF-75005 ParisFrance i2S 28-30 rue Jean Perrin 33608 PessacFrance Centre de Nanosciences et de Nanotechnologies(C2N) CNRS UMR 9001Universite Paris-Saclay91120 PalaiseauFrance Institut d'Electronique et des Systemes CNRS(UMR 5214)Univ Montpellier860 rue de Saint-Priest34095 Montpellier Cedex 5France

Optically driven photoconductive switches are one of the predominant sources currently used in terahertz im-aging ***,owing to their low average powers,only raster-based images can be taken,resulting in slow *** this work,we show that by placing a photoconductive switch within a cavity,we are able to generate absolute average THz powers of 181μW with the frequency of the THz emission centered at 1.5 THz-specifications ideally adapted to applications such as non-destructive *** cavity is based on a metal-insulator-metal structure that permits an en hancement of the average power by almost 1 order of magnitude compared to a standard structure,while conserving a broadband spectral *** demonstrate proof-of-principle real-time imaging using this source,with the broadband spectrum permitting to eliminate strong diffraction artifacts.

关键词： photoconductive sources cavity

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地壳流变结构控制作用下的龙门山断裂带地震发生机理

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地球物理学报 2014年第2期57卷 404-418页

作者：柳畅石耀霖朱伯靖程惠红杨小林华中科技大学物理学院地球物理研究所武汉430074 laboratoire de Gfiologie CNRS-UMR8538 ecole Normale Superieure Paris 75231 中国科学院大学中国科学院计算地球动力学重点实验室北京100049 陕西省地震局西安710068

青藏高原东缘低地形变速率的龙门山断裂带上相继发生了2008汶川Mw7.9级地震和2013芦山Mw6.6级地震.地震勘探与震源定位结果揭示了龙门山区域地震空间分布特征:纵向上,龙门山断裂带这两次地震主震均发生在龙门山断裂带上地壳的底部(14～1... 详细信息

青藏高原东缘低地形变速率的龙门山断裂带上相继发生了2008汶川Mw7.9级地震和2013芦山Mw6.6级地震.地震勘探与震源定位结果揭示了龙门山区域地震空间分布特征:纵向上,龙门山断裂带这两次地震主震均发生在龙门山断裂带上地壳的底部(14～19km),绝大部分余震均发生在上地壳范围(5～25km),而在其中、下地壳深度范围内鲜见余震发生;横向上,地震(Mw>3)在龙门山断裂带青藏高原一侧密集分布且曾有大震发生,而四川盆地地震稀少(Mw>3).为探讨龙门山断裂带地震发生机理,并解释以上龙门山区域地震空间分布特征,本文建立了龙门山断裂带西南段跨芦山地震震中区域的四种不同流变结构的龙门山断裂带三维岩石圈模型,以地表GPS观测资料为约束边界条件,数值模拟龙门山断裂带岩石圈在数千年以上长期匀速构造挤压作用下的应力积累特征,探讨了地壳分层流变性质对地壳应力积累的影响,分析了该区域地震空间分布与构造应力积累速率的关系.计算结果表明:该区域在数千年的应力积累过程中,脆性上地壳中应力表现近于恒定值的线性增长趋势,龙门山断裂带上地壳底部出现应力集中积累现象,这一应力集中现象可以解释龙门山断裂带汶川地震与芦山地震主震的发生,及其大部分余震在脆性上地壳中的触发;青藏高原一侧上地壳应力积累速率远远高于四川盆地的应力积累速率,这一应力积累分布现象可以解释龙门山区域青藏高原一侧地震密集而四川盆地地震稀少的地震空间分布特征;通过比较不同流变结构模型中的应力积累状态,认为导致这一应力积累空间分布状态的重要控制因素在于青藏高原中、下地壳较低的黏滞系数与四川盆地中、下地壳较高的黏滞系数的差异.在柔性的中、下地壳内,应力增长近于指数形式,稳定状态之后其应力增长速率近于零,构造应力积累难以达到岩石破裂强度,因而鲜见地震发生.地壳各层位的应力增长率差异与地震成层分布的现象共同揭示了龙门山区域岩石圈分层流变结构:脆性上地壳、韧性中、下地壳(青藏高原一侧较弱,四川盆地一侧较强)、韧性岩石圈上地幔.

关键词：龙门山断裂带汶川地震芦山地震应力集中黏性差异 Moho面突变

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Late Miocene–Pliocene Paleoclimatic Evolution Documented by Terrestrial Mollusk Populations in the Western Chinese Loess Plateau

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Late Miocene–Pliocene Paleoclimatic Evolution Documented by...

Numerical Simulation of Cu（In,Ga）Se2 Solar Cells Performances

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Fengjiang Li Naiqin Wu denis-Didier Rousseau Yajie Dong Dan Zhang Yunpeng Pei Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences laboratoire de Meteorologie Dynamique UMR INSU-CNRS 8539 & CERES-ERTI Ecole Normale Superieure Lamont-Doherty Earth Observatory of Columbia University School of the Earth Sciences and Resources China University of Geosciences

The Neogene eolian deposits in the Chinese Loess Plateau(CLP) are one of the most useful continental deposits for understanding climatic changes. To decipher Late Neogene paleoclimatic changes in the CLP, we present a terrestrial mollusk record spanning the time interval between 7.1 and 3.5 Ma from the western CLP. The results indicate four stages of paleoclimatic evolution: From 7.1 to 6.2 Ma, cold and dry climatic conditions prevailed as evidenced by high values of the total number of cold-aridiphilous(CA) mollusk species and by low values of all of the thermo-humidiphilous(TH) mollusk indices. From 6.2 to 5.4 Ma, the climate remained cold and dry but was not quite as dry as during the preceding phase, as indicated by the dominance of CA mollusks and more TH species and individuals. From 5.4 to 4.4 Ma, a warm and moist climate prevailed, as indicated by high values of the TH species and individuals and by the sparsity of CA species and individuals. From 4.4 to 3.5 Ma, all of the CA indices increased significantly and maintained high values;all of the TH indices exhibit high values from 4.4 to 4.0 Ma, an abrupt decrease from 4.0 Ma and a further increase from 3.7 Ma. The CA species of Cathaica pulveraticula, Cathaica schensiensis, and Pupopsis retrodens are only identified in this stage, indicating that the CA species were diversified and that the climate was becoming drier. Moreover, the CA mollusk group exhibits considerable diversity from 7.1 to 5.4 Ma when a cold, dry climate prevailed;whereas the diversity of the TH group was high during the relatively warm, wet interval from 5.4 to 4.4 Ma. This indicates that variations in the diversity of the CA and TH mollusk groups were closely related to climatic changes during the Late Miocene to Pliocene.

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Journal of Energy and Power Engineering 2015年第12期9卷 1047-1055页

作者： Daouda Oubda Marcel Bawindsom Kebre Francois Zougmore Donatien Njomo Frederic Ouattara LA.M.E (laboratoire de Materiaux et Environnement) UFR-SEA (Unite de Formation et de Recherche en Sciences Exactes et Appliquees) Universite de Ouagadougou Ouaga 03 BP 7021 Burkina Faso L.A.T.E.E (laboratoire d'Analyse des Technologies de l'Energie et de l'Environnement)-FAST (Faculte des Sciences et Techniques)-Sciences Universite Yaounde I Yaounde 812 Cameroun LA.R.E.M.E (laboratoire de Recherche en Energdtique et Meteorologie de l'Espace) ENS (Ecole Normale Superieure) Universite de Koudougou Koudougou BP 376 Burkina Faso

This paper presents a numerical characterization of copper-indium-gallium-diselenide thin film solar cells using one dimensional simulation program （SCAPS-1D）. We have performedan optimization of the performances of the standard Mo/Cu（In, Ga）Se2/CdS/ZnO solar cells using current-voltage and quantum efficiency methods. With a CuIn..7Ga0.3Se2 absorber, we have investigated the buffer layer thickness, temperature, series and shunt resistances effects on the open-circuit voltage, short-circuit current density, fill factor, conversion efficiency and quantum efficiency. The simulated results show good performances when the thickness of the buffer layer is in the range of 10-40 um due to the reduction of absorption in the short wavelenghts （380-500 nm）. High performances of the model is obtained when the series and shunt resistances is in the range of 0.1-1 Ω·cm^2 and 1,000 Ω·cm^2, respectively. Under these conditions, the cell can theoretically operate under an ambiant temperature of 370 K without any loss of its performances.

关键词： Numerical simulation SCAPS-1D CdS thickness temperature Rs Rsh