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Potential generated by a massive inhomogeneous straight segment

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Research in Astronomy and Astrophysics 2011年第3期11卷 345-352页

作者： nour-eddine Najid El Haj Elourabi Mohamed Zegoumou Equipe Mécanique Statistique et Astronomie-Laboratoire de Physique Théorique et Appliquée Université Hassan Ⅱ Ain Chock-Faculté des Sciences Ain Chock BP 5366 Maarif Casablanca Morocco

The discoveries of binary asteroids have opened an important new field of research concerning the calculation of potential generated by irregular *** of them have an elongated shape.A simple model to describe the motion of a test particle in that kind of potential requires consideration of a finite homogeneous straight *** construct this model by adding an inhomogeneous distribution of mass. To be consistent with the geometrical shape of the asteroid,we explore a parabolic profile of the *** establish the closed analytical form of the potential generated by this inhomogeneous massive *** study of the dynamical behavior is fulfilled by the use of Lagrangian formulation,which allows us to calculate some two and three dimensional orbits.

关键词： asteroids—potential—inhomogeneous distribution

Microstructure and Magnetic Properties of Fe-Ni Alloy Fabricated by Selective Laser Melting Fe/Ni Mixed Powders

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Journal of Materials Science & Technology 2013年第8期29卷 757-760页

作者： Baicheng Zhang nour-eddine Fenineche Hanlin Liao Christian Coddet LERMPS Universit de Technologie de Belfort-MontbliardSite de SvenansBelfort Cedex 90010France

Fe-Ni alloy, as a widely applied ferromagnetic material, is synthesized using selective laser melting （SLM）. The chemical compositions and microstructure of the SLM Fe-Ni alloy are characterized by X-ray diffraction （XRD）, energy dispersive X-ray spectroscopy and scanning electron microscopy. It was found that the samples exhibited fine grains with homogenous distribution when a low laser scanning velocity was used. Moreover, the magnetic properties of the samples with different laser parameters are also measured. It shows that the SLM Fe-30%Ni alloy possesses a low coercivity and high saturation magnetization. It also can be obtained that SLM is an alternative faster method to prepare soft magnetic material with complex shapes. Moreover, the magnetic properties can be influenced by the laser parameters.

关键词： Selective laser melting (SLM) Fe-Ni alloy Soft magnetic materials Magnetic property

A Flocking-Based on Demand Routing Protocol for Unmanned Aerial Vehicles

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Journal of Computer Science & Technology 2018年第2期33卷 263-276页

作者： nour El Houda Bahloul Saadi Boudjit Marwen Abdennebi Djallel eddine Boubiche LaSTIC Laboratory University of Batna 2 Batna 05078 Algeria L2TI Laboratory University of Paris 13 Villetaneuse 93430 France

The interest shown by some community of researchers to autonomous drones or UAVs （unmanned aerial vehicles） has increased with the advent of wireless communication networks. These networks allow UAVs to cooperate more efficiently in an ad hoc manner in order to achieve specific tasks in specific environments. To do so, each drone navigates autonomously while staying connected with other nodes in its group via radio links. This connectivity can deliberately be maintained for a while constraining the mobility of the drones. This will be suitable for the drones involved in a given path of a given transmission between a source and a destination. This constraint could be removed at the end of the transmission process and the mobility of each concerned drone becomes again independent from the others. In this work, we proposed a flocking-based routing protocol for UAVs called BR-AODV. The protocol takes advantage of a well known ad hoc routing protocol for on-demand route computation, and the Boids of Reynolds mechanism for connectivity and route maintaining while data is being transmitted. Moreover, an automatic ground base stations discovery mechanism has been introduced for a proactive drones and ground networks association needed for the context of real-time applications. The performance of BR-AODV was evaluated and compared with that of classical AODV routing protocol and the results show that BR-AODV outperforms AODV in terms of delay, throughput and packet loss.

关键词： unmanned aerial vehicle (UAV) AODV Boids of Reynolds mobility control

Remarkable Link between Projected Uncertainties of Arctic Sea-Ice Decline and Winter Eurasian Climate

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Advances in Atmospheric Sciences 2018年第1期35卷 38-51页

作者： Hoffman H.N.CHEUNG Noel KEENLYSIDE nour-eddine OMRANI Wen ZHOU Geophysical Institute University of BergenBergen 5007Norway Bjerknes Centre for Climate Research University of BergenBergen 5007Norway Nansen Environmental and Remote Sensing Center Bergen 5006Norway Guy Carpenter Asia-Pacific Climate Impact Centre School of Energy and EnvironmentCity University of Hong KongHong KongChina City University of Hong Kong Shenzhen Research Institute Shenzhen 518057China

We identify that the projected uncertainty of the pan-Arctic sea-ice concentration(SIC) is strongly coupled with the Eurasian circulation in the boreal winter(December–March; DJFM), based on a singular value decomposition(SVD) analysis of the forced response of 11 CMIP5 models. In the models showing a stronger sea-ice decline, the Polar cell becomes weaker and there is an anomalous increase in the sea level pressure(SLP) along 60°N, including the Urals–Siberia region and the Iceland low region. There is an accompanying weakening of both the midlatitude westerly winds and the Ferrell cell,where the SVD signals are also related to anomalous sea surface temperature warming in the midlatitude North *** the Mediterranean region, the anomalous circulation response shows a decreasing SLP and increasing precipitation. The anomalous SLP responses over the Euro-Atlantic region project on to the negative North Atlantic Oscillation–like ***, pan-Arctic SIC decline could strongly impact the winter Eurasian climate, but we should be cautious about the causality of their linkage.

关键词： Arctic climate Siberian high Icelandic low three-cell meridional circulation

Book Review of Green Materials for Sustainable Water Remediation and Treatment

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Green and Sustainable Chemistry 2014年第3期4卷 175-176页

作者： nour-eddine Es-Safi Mohammed V Agdal University Rabat Morocco

Water is one of the most important substances on earth. Safe drinking water is essential to humans and other life forms. All plants and animals must have water to survive. If there was no water, there would be no life on earth. Apart from drinking it to survive, people have many other uses for water. This natural resource is becoming scarcer and its demand exceeds supply in some region rendering its availability a major social and economic concern. Apart of this scarcity is water pollution which is increasing day by day in many parts of the world. Sources of fresh water on land are getting more and more polluted than ever before. As a result, contaminated water became unsuitable for use. Poor water quality is deadly since contaminated water causes hazards to public health through poisoning or the spread of disease. In order to address these issues, the practice of water remediation has been developed.

关键词： Water Water Remediation Pollution

Structural and Electronic Properties of Bixo<sub>3</sub>(X = Mn, Fe, Cr)

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Journal of Modern Physics 2011年第7期2卷 642-650页

作者： Djillali Bensaid nour-eddine Benkhettou Ali Kourdassi Laboratoire des Materiaux Magnetiques Faculty of Sciences University of Sidi Bel Abbes

The candidate multiferroic BiCrO3 and its chemical neighbors BiMnO3 and BiFeO3 are known to be ferromagnetic and ferroelectric respectively. With structural distortions driven by the strongly polarizable Bi ions, we present results of the first-principles density functional calculations using the (FP-LMTO) method with the spin-orbit coupling for those materials in the pseudo-cubic perovskite phase. The results showed that the valence bands in these compounds are formed by the 6p orbitals of bismuth and 3d orbital’s of the transition metals. Our results indicate that these materials have metallic behavior for spin-up polarization but being a clear tandance for semiconductor spin-down BiMnO3.

关键词： Multiferroics Perovskite Density Functional Theory ABO3 Oxide Perovskites

Ferroelectric solid solution Li1-xTa1-xWxO3 as potential photocatalysts in microbial fuel cells:Effect of the W content

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Chinese Journal of Chemical Engineering 2018年第9期26卷 1985-1991页

作者： Abdellah Benzaouak nour-eddine Touach V.M.Ortiz-Martinez M.J.Salar-Garcia F.Hernandez-Fernandez A.P.de los Rios Mohammed El Mahi El Mostapha Lotfi Laboratory of Mechanics and Industrial Processes Chemical Sciences Research TeamENSETMohammed V University in RabatMorocco Department of Chemical and Environmental Engineering Technical University of CartogenaCampus Muralla Del Mar MurdaSpain

Microbial fuel cells(MFCs)are bio-electrochemical systems that can directly convert the chemical energy contained in an effluent into bioelectricity by the action of *** performance of these devices is heavily impacted by the choice of the material that forms the *** work focuses on the assessment of ferroelectric and photocatalytic materials as a new class of non-precious catalysts for MFC cathode construction.A series of cathodes based on mixed oxide solid solution of LiTaO_3with WO_3formulated as Li_(1-x)Ta_(1-x)W_xO_3(x=0,0.10,0.20 and0.25),were prepared and investigated in *** catalyst phases were synthesized,identified and characterized by DRX,PSD,MET and UV–Vis absorption *** cathodes were tested as photoelectrocatalysts in the presence and in the absence of visible light in devices fed with industrial *** results revealed that the catalytic activity of the cathodes strongly depends on the ratio of substitution of W^(6+)in the LiTaO_*** maximum power densities generated by the MFC working with this series of cathodes increased from60.45 mW·m^(-3)for x=0.00(LiTaO_3)to 107.2 mW·m^(-3)for x=0.10,showing that insertion of W^(6+)in the tantalate matrix can improve the photocatalytic activity of this ***,MFCs operating under optimal conditions were capable of reducing the load of chemical oxygen demand by 79%(COD_(initial)=1030 mg·L^(-1)).

关键词：光催化剂铁电体微生物房间燃料混合氧化物直接变换电气化学

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微波固相法合成的苯并噁嗪及其共混树脂性能

微波固相法合成的苯并噁嗪及其共混树脂性能

第17届全国复合材料学术会议

作者：顾奕祖龙吟袁荞龙 ElMansouri nour-eddine 黄发荣华东理工大学材料科学与工程学院

邻位二烷基取代苯胺与苯酚和多聚甲醛在100W下微波辐照20min合成了五种苯并噁嗪单体,将其中邻位为甲基和乙基取代的苯胺型苯并噁嗪与双酚A型苯并噁嗪(BAF)共混。结果表明,在100-250℃内邻二甲基苯胺型苯并噁嗪(2m6m-BZ)与BAF以3:7摩尔... 详细信息

邻位二烷基取代苯胺与苯酚和多聚甲醛在100W下微波辐照20min合成了五种苯并噁嗪单体,将其中邻位为甲基和乙基取代的苯胺型苯并噁嗪与双酚A型苯并噁嗪(BAF)共混。结果表明,在100-250℃内邻二甲基苯胺型苯并噁嗪(2m6m-BZ)与BAF以3:7摩尔比共混物的粘度低于500mPa.s,该共混树脂固化后热性能接近纯BAF树脂,共混树脂的介电常数小于3.9,介电损耗低于0.0035,其介电性能优于其它共混树脂。

关键词：微波固相合成苯并噁嗪共混热性能介电性能

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微波固相法合成苯并恶嗪及其共混树脂的性能

热固性树脂 2013年第2期28卷 6-12页

作者：顾奕祖龙吟袁荞龙 El Mansouri nour-eddine 黄发荣华东理工大学材料科学与工程学院特种功能聚合物及相关技术教育部重点实验室上海200237

邻位二烷基取代苯胺与苯酚和多聚甲醛经100 W微波辐照20 min反应得到了5种苯并恶嗪单体,将其中邻位为甲基和乙基取代的苯胺型苯并恶嗪与双酚A型苯并恶嗪(BAF)共混,采用红外光谱(FT-IR)、核磁共振氢谱(1H-NMR)、示差扫描量热仪(DSC)、动... 详细信息

邻位二烷基取代苯胺与苯酚和多聚甲醛经100 W微波辐照20 min反应得到了5种苯并恶嗪单体,将其中邻位为甲基和乙基取代的苯胺型苯并恶嗪与双酚A型苯并恶嗪(BAF)共混,采用红外光谱(FT-IR)、核磁共振氢谱(1H-NMR)、示差扫描量热仪(DSC)、动态机械分析(DMA)、热失重分析仪(TGA)、粘度仪和介电阻抗仪研究了共混树脂的粘温性、热性能及介电性能。结果表明,邻二甲基苯胺型苯并恶嗪(2m6m-BZ)与BAF以物质的量比3∶7共混的体系100～250℃下粘度<500 mPa.s,其固化后热性能接近固化后的纯BAF树脂,且介电常数<3.9,介电损耗低于0.003 5,优于其它共混树脂。

关键词：微波固相合成苯并恶嗪共混热性能介电性能