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轮廓仪法测量大镜面及纳精度表面轮廓仪研发

江西科学 2023年第4期41卷 736-739页

作者：李剑白钱石南李小芸 mourad Idir 江西省科学院南昌330096 布鲁克海文国家实验室 11973NYUSA

指出了表面轮廓仪法检测大尺寸光学反射镜的重要意义,论述高精度表面轮廓仪系列分类。新的第3代表面轮廓仪NSP研发解决了较深弯曲反射镜的超高精度测试难题。当ELCOMAT 3000/10自准直仪在50 mm固定距离精密较正后,NSP即可能达到50 nrad ... 详细信息

指出了表面轮廓仪法检测大尺寸光学反射镜的重要意义,论述高精度表面轮廓仪系列分类。新的第3代表面轮廓仪NSP研发解决了较深弯曲反射镜的超高精度测试难题。当ELCOMAT 3000/10自准直仪在50 mm固定距离精密较正后,NSP即可能达到50 nrad rms检测精度。

关键词：表面轮廓仪大尺寸反射镜测试纳精度第3代表面轮廓仪

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Water Status in the Syrian Water Basins

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Open Journal of Modern Hydrology 2012年第1期2卷 15-20页

作者： Khaldoon A. mourad Ronny Berndtsson 不详

Syrian water resources face economic and physical water scarcity. This together with a large population and development increase and the climate change may lead to increasing risks for international controversies and disputes in the coming decades. According to FAO, the available water resource per capita AWPC is going to be half by 2025. Depending on its seven water basins, this paper analyses water demand and supply in the Syria with their projections till 2050. The paper shows that two of the seven Syrian basins need a specific concern as they face water scarcity problem. However, two basins have extra water. Therefore, the paper focuses on the need for a sustainable water management, which takes all nonconventional water resources into account to contribute in the Syrian water balance such as rainwater harvesting and wastewater reuse.

关键词： Renewable water Middle East Sanitation Water harvesting

Measurement of muon-induced neutron yield at the China Jinping Underground Laboratory

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Chinese Physics C 2022年第8期46卷 211-219页

作者：赵林骆文泰 Lars Bathe-Peters 陈少敏 mourad Chouaki 窦威郭磊郭子溢 Ghulam Hussain 李进京梁晔刘倩罗光祁鸣邵文辉唐健万林焱王喆武益阳续本达徐彤徐蔚然杨玉梓 Minfang Yeh 张爱强张彬 JNE collaboration Department of Engineering Physics Tsinghua UniversityBeijing 100084China Center for High Energy Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle&Radiation Imaging(Tsinghua University) Ministry of EducationChina Institut für Physik Technische Universität BerlinBerlin 10623Germany École Polytechnique Fédérale de Lausanne Lausanne 1015Switzerland School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Physics Sun Yat-Sen UniversityGuangzhou 510275China School of Physics Nanjing UniversityNanjing 210093China Brookhaven National Laboratory UptonNew York 11973USA 不详

Solar,terrestrial,and supernova neutrino experiments are subject to muon-induced radioactive *** China Jinping Underground Laboratory(CJPL),with its unique advantage of a 2400 m rock coverage and long distance from nuclear power plants,is ideal for MeV-scale neutrino *** a 1-ton prototype detector of the Jinping Neutrino Experiment(JNE),we detected 3 43 high-energy cosmic-ray muons and(7.86±3.97)muon-induced neutrons from an 820.28-day dataset at the first phase of CJPL(CJPL-I).Based on the muon-induced neutrons,we measured the corresponding muon-induced neutron yield in a liquid scintillator to be(3.44±1.86_(stat.)±0.76_(syst.))×10^(-4) μ^(-1)g^(-1)cm^(2) at an average muon energy of 340 *** provided the first study for such neutron background at CJPL.A global fit including this measurement shows a power-law coefficient of(0.75±0.02) for the dependence of the neutron yield at the liquid scintillator on muon energy.

关键词： Underground laboratory neutrino detector cosmic-ray muon neutron yield liquid scintillator

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Environmental Impact of Mining Exploitation: A Case Study of Some Mines of Barite in the Eastern Anti-Atlas of Morocco

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Journal of Environmental Protection 2016年第11期7卷 1473-1482页

作者： abdelhafid Essalhi mourad Essalhi Abdeslam Toummite Equipe de Recherche: Géophysique Géoressources et Patrimoine (ER-GGP) Département de Géologie Faculté des Sciences et Techniques Errachidia Maroc

Extraction of mineral resources is the backbone of the national economy in many developed and developing countries of the world. However, the exploitation can have many negative impacts on the immediate environment of the exploitation sites. In this study performed on some mining areas of the Moroccan Anti-Atlas, four principal negative effects were detected: effect on the physiognomy, on safety, on health, and on recovery rate. The principal source of this situation is the exploitation of the ore deposits from top to bottom without using any geological preparation and the use of non-adapted exploitation technics. To minimize these impacts, we propose to establish a geological study and advanced mining exploration before starting exploitation, and follow an exploitation technic well adapted to the morphology of the ore deposit like cut-and-fill mining and sublevel stoping methods.

关键词： Negative Impacts Environment Exploitation Physiognomy Anti-Atlas

Indium doping effect on properties of ZnO nanoparticles synthesized by sol–gel method

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Chinese Physics B 2019年第4期28卷 342-348页

作者： S mourad J El Ghoul K Omri K Khirouni Laboratory of Physics of Materials and Nanomaterials Applied at Environment (LaPhyMNE) Faculty of Sciences in Gabes Gabes University Imam Mohammad Ibn Saud Islamic University (IMSIU) College of Sciences Department of Physics

Pure ZnO and indium-doped ZnO(In–ZO) nanoparticles with concentrations of In ranging from 0 to 5% are synthesized by a sol–gel processing technique. The structural and optical properties of ZnO and In–ZO nanoparticles are characterized by different techniques. The structural study confirms the presence of hexagonal wurtzite phase and indicates the incorporation of In^(3+) ions at the Zn^(2+) sites. However, the optical study shows a high absorption in the UV range and an important reflectance in the visible range. The optical band gap of In–ZnO sample varies between 3.16 e V and 3.22 e V. The photoluminescence(PL) analysis reveals that two emission peaks appear: one is located at 381 nm corresponding to the near-band-edge(NBE) and the other is observed in the green region. The aim of this work is to study the effect of indium doping on the structural, morphological, and optical properties of ZnO nanoparticles.

关键词： In-doped ZnO nanoparticles sol–gel process structural and optical characterization

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Electromagnetic Modulation of Dipole Antenna inside an Infinite Rectangular Waveguide Using MoM-GEC

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Journal of Electromagnetic Analysis and Applications 2016年第9期8卷 161-172页

作者： Hafawa Messaoudi Aidi mourad Taoufik Aguili Communication System Laboratory Sys’Com National Engineering School of Tunis University of Tunis El Manar Tunis Tunisia

A theoretical and modulation study of a dipole antenna located in rectangular waveguide is presented. The aim is to determine the nature and dimensions which allow us to attain the simulations in free space. We compare the behavior of a dipole antenna modeled by MOM-GEC with those obtained in free space. A method of moment (MoM) approach combined to the generalized equivalent circuit (GEC) modeling is applied to compute the input impedance of a dipole antenna resonating at 1.8 GHz. A parametric study is conducted to investigate the wall effects on the antenna performances. Also we study the convergence of the input impedance as a function of test function number. The current values with integral method (MOM) are compared with the computed values obtained from numerical methods such as the combined MOM-GEC. The simulated values agree with values obtained from numerical methods.

关键词： Communication System Laboratory Sys’Com National Engineering School of Tunis University of Tunis El Manar Tunis Tunisia

Improving Class Cohesion Measurement: Towards a Novel Approach Using Hierarchical Clustering

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Journal of Software Engineering and Applications 2012年第7期5卷 449-458页

作者： Lazhar Sadaoui mourad Badri Linda Badri Software Engineering Research Laboratory Department of Mathematics and Computer Science University of Quebec Trois-Rivières Canada

Class cohesion is considered as one of the most important object-oriented software attributes. High cohesion is, in fact, a desirable property of software. Many different metrics have been suggested in the last several years to measure the cohesion of classes in object-oriented systems. The class of structural object-oriented cohesion metrics is the most in-vestigated category of cohesion metrics. These metrics measure cohesion on structural information extracted from the source code. Empirical studies noted that these metrics fail in many situations to properly reflect cohesion of classes. This paper aims at exploring the use of hierarchical clustering techniques to improve the measurement of cohesion of classes in object-oriented systems. The proposed approach has been evaluated using three particular case studies. We also used in our study three well-known structural cohesion metrics. The achieved results show that the new approach appears to better reflect the cohesion (and structure) of classes than traditional structural cohesion metrics.

关键词： Object-Oriented Classes Cohesion Similarity Clustering Metrics and Empirical Evaluation

Effect of water extract of dates palm (Phoenix dactylifera) on semen characteristics and oxidative status in serum of male New Zealand rabbits under heat stress

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Asian pacific Journal of Reproduction 2018年第1期7卷 22-26页

作者： Walaa H Khalifa Gamal A El-Sisy Walid S El-Nattat AAA mourad Nagwa Maghraby Animal Production Department Agricultural and Biological Researches DivisionNational Research CentreDokkiGizaEgypt Animal Reproduction and Artificial Insemination Department Veterinary Researches DivisionNational Research CentreGizaEgypt

Objective: To estimate the effects of the water extract of dates palm (Phoenix dactylifera) (DWE) on sperm quality parameters, testosterone level and serum antioxidants activities of New Zealand rabbits under heat stress. Methods: A total of 30 bucks of New Zealand White rabbits were randomly divided into three equal groups as follows: Group 1 was treated as control group and fed on balanced commercial ration. Groups 2 and 3 were treated with 10 and 20 mL of dates extract substituting water in the early morning before watering and fed on balanced commercial ration. This schedule was performed daily for 5 days/week, for an experimental period of 5 weeks. Fertility parameters such as reaction time, potential of hydrogen ion (pH), mass motility, individual progressive motility %, percentage of live sperm and abnormal sperm (%) were measured. Blood serum testosterone level, serum glutathione reduced, nitric oxide, ascorbic acid and malondialdehyde were also determined. Results: The daily oral administration of 10 mL DWE significantly increased the pH, the mass motility and individual progressive motility % compared to the control group. Although, the consumption of 20 mL DWE significantly (P<0.0001) increased the live sperm% and decreased the abnormal sperm % compared to the other two treatments. The administration of date extracts (10 and 20 mL) had significantly (P<0.0001) decreased nitric oxide and glutathione reduced levels compared to the control. On the other hand, it increased significantly the lipid peroxidation, ascorbic acid and testosterone level compared to the control. Conclusions:The aqueous extract of date palm (10-20 mL) could enhance the rabbit bucks fertility and its health performance.

关键词： Phoenix dactylifera Rabbit bucks Semen Testosterone Antioxidant

A New Approach Based on MoM-GEC Method to Mutual Coupling Analysis of Symmetric Twin Waveguides for Antenna Applications

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Journal of Electromagnetic Analysis and Applications 2015年第12期7卷 283-290页

作者： Abdessalem Kaddouri mourad Aidi Taoufik Aguili Communication System Laboratory Sys’Com National Engineering School of Tunis University Tunis El Manar Tunis Tunisia

In previous modeling works, the waveguide radiation in the free space is modeled using an infinite flange in aperture plan. In this paper, we propose a new formulation to analyze the radiation of twin rectangular waveguides in free space. Our formulation consists firstly in simulating the free space as rectangular waveguide and seeking the appropriate dimensions that do not affect scattering parameters. In the second step, we use the symmetry principle to reduce the coupling problem to single guide radiating in the free space. Moreover, for more simplification, we consider a concentric discontinuity to solve this latter. This approach is based on moments method combined to the generalized equivalent circuit method (MoM-GEC) in order to reduce the number of unknown problems and alleviate their computation. Obtained numerical results are presented and discussed. A good agreement with literature is shown and the boundary conditions are verified.

关键词： Waveguide Coupling MoM-GEC Propagation Scattering Electric Field