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Groundwater quality assessment using multivariate analysis,geostatistical modeling, and water quality index(WQI): a case of study in the Boumerzoug-El Khroub valley of Northeast Algeria

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Acta Geochimica 2019年第6期38卷 796-814页

作者： oualid Bouteraa Azeddine Mebarki Foued Bouaicha Zeineddine Nouaceur Benoit Laignel Laboratory of Geology and Environment(LGE) Uni versite Freres Mentouri Constantine 1ConstantineAlgeria Department of Natural and Life Sciences Mohamed Boudiaf UniversityM'silaAlgeria LASTERNE Laboratory Universite Freres Mentouri Constantine 1ConstantineAlgeria UMR IDEES CNRS 6226 Universite de Rouen1 Rue Thomas Becket76821 Saint Aignan CedexFrance UMR CNRS 6143 M2C Department of GeologyUniversity of Rouen1 Rue Thomas Becket76821 Saint Aignan CedexFrance

In this study,the analytical data set of 26 groundwater samples from the alluvial aquifer of Boumerzoug-E1 khroub valley has been processed simultaneously with Multivariate analysis,geostatistical modeling,WQI,and geochemical *** analysis identified three main water types based on the major ion contents,where mineralization increased from group 1 to group *** groups were confirmed by FA/PCA,which demonstrated that groundwater quality is influenced by geochemical processes(water-rock interaction)and human practice(irrigation).The exponential semivariogram model *** chemistry has a strong spatial structure for Mg,Na,Cl,and NO3,and a moderate spatial structure for EC,Ca,K,HCO3,and *** quality maps generated using ordinary Kriging are consistent with the HCA and PCA *** water groups are supersaturated with respect to carbonate minerals,and dissolution of kaolinite and Ca-smectite is one of the processes responsible for hydrochemical evolution in the area.

关键词： Groundwater Multivariate analysis Geostatistical modeling Geochemical modeling Mineralization Ordinary Kriging

Synthesis and Characterization of In Situ(Al_2O_3–Si)/Al Composites by Reaction Hot Pressing

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Acta Metallurgica Sinica(English Letters) 2014年第5期27卷 930-936页

作者： El oualid Mokhnache Guisong Wang Lin Geng Balasubramaniam Kaveendran Lujun Huang School of Materials Science and Engineering Harbin Institute of Technology

In situ （Al2O3-Si）/Al composites with a reinforcement volume fraction of 10% were synthesized from the Al-SiO2 system using low energy ball milling and reaction hot pressing. Differential thermal analysis was used to investigate the reaction mechanisms between SiO2 and Al. X-ray diffraction results revealed that the reaction between Al and SiO2 took place completely at 900 ℃ with a holding time of 2 h, thereby forming Al2O3 and Si. Scanning electron microscopic, energy dispersive X-ray spectroscopic, and transmission electron microscopic （TEM） results showed that the in situ synthesized A1203 and Si particles, whose sizes are less than 2 μm, were polygonal in shape and dispersed uniformly in the matrix. Moreover, Al2O3 particle size showed a tendency to increase from - 2 to - 6 μm when the synthesis temperature was increased. Furthermore, TEM observation showed that the interface between the reinforcements and Al matrix is clean. The yield strength, ultimate tensile strength, and Brinell hardness of the in situ （Al2O3-Si）/Al composite was significantly higher than the aluminum matrix. Mechanisms governing the tensile fracture process are discussed.

关键词： Al composites Microstructure Al2O3 Silicon

In situ(α-Al_2O_3+ZrB_2)/Al composites with network distribution fabricated by reaction hot pressing

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International Journal of Minerals,Metallurgy and Materials 2015年第10期22卷 1092-1100页

作者： El oualid Mokhnache Gui-song Wang Lin Geng Kaveendran Balasubramaniam Abdelkhalek Henniche Noureddine Ramdani School of Materials Science and Engineering Harbin Institute of Technology Polymer Materials Research Center Harbin Engineering University

In situ（α-Al2O3+ZrB2）/Al composites with network distribution were fabricated using low-energy ball milling and reaction hot pressing. Differential thermal analysis（DTA） was used to study the reaction mechanisms in the Al–Zr O2–B system. X-ray diffraction（XRD） and scanning electron microscopy（SEM） in conjunction with energy-dispersive X-ray spectroscopy（EDX） were used to investigate the composite phases, morphology, and microstructure of the composites. The effect of matrix network size on the microstructure and mechanical properties was investigated. The results show that the optimum sintering parameters to complete reactions in the Al–Zr O2–B system are 850°C and 60 min. In situ-synthesized α-Al2O3 and Zr B2 particles are dispersed uniformly around Al particles, forming a network microstructure; the diameters of the α-Al2O3 and Zr B2 particles are approximately 1–3 μm. When the size of Al powder increases from 60–110 μm to 150–300 μm, the overall surface contact between Al powders and reactants decreases, thereby increasing the local volume fraction of reinforcements from 12% to 21%. This increase of the local volume leads to a significant increase in microhardness of the in situ（α-Al2O3–Zr B2）/Al composites from Hv 163 to Hv 251.

关键词： metal matrix composites network distribution sinte

Evaluation of phase change materials for a light-weight building in Morocco:Effect of building’s volume,window orientation&infiltration

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Energy and Built Environment 2024年第6期5卷 863-877页

作者： Imad Ait Laasri Niima Es-sakali Abdelkader Outzourhit Mohamed oualid Mghazli Laboratory(LaMEE) Faculty of Sciences SemlaliaCadi Ayyad UniversityMarrakeshMorocco Laboratory(LMAID) Rabat National School of MineRabatMorocco Green Energy Park(UM6P/IRESEN) km2 R206BenguerirMorocco ENTPE LTDS UMR CNRS 5513Universitéde LyonCedexVaulx-en-VelinFrance

In this study,we will model a light-weight building made of phase change materials(PCMs)to analyze the impact of the building volume,window orientation,and air infiltration on the PCM *** is done by calculating the energy savings attained by the use of PCM across all of ***’ll use the commercial Rubitherm panels with RT28HC as a phase change material in this ***,the EnergyPlus simulation engine is chosen to perform the *** impact of building volumes is also evaluated on the PCM activation for light-weight square buildings with different side lengths of 10 m,9 m,8 m,and 7 ***,we looked at how well the PCM performed in terms of energy savings and thermal regulation at different window orientation placements(south,north,west,and east)and various air infiltration rates(0.5,1,1.5,and 3 ACH).This paper’s primary objective is to determine the energy savings for the PCM-enhanced building in Morocco,as well as the effect of building volume,window orientation,and infiltration on the PCM capabilities for stabilizing the indoor room *** results show good indoor temperature stabilization during the summer,for the light-weight square building with a south-facing window and no air *** configuration was able to achieve a total fluctuation reduction of 1303.3℃for the 10 m building in a semi-arid ***,a high energy savings percentage of 69.56%was achieved for the PCM-enhanced building with the south-oriented window and air infiltration of 0.5 air change per hour.

关键词： Building energy efficiency Phase change materials Passive thermal regulation

Geochemical assessment, mixing behavior and environmental impact of thermal waters in the Guelma geothermal system,Algeria

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Acta Geochimica 2019年第5期38卷 683-702页

作者： Foued Bouaicha Henia Dib oualid Bouteraa Nabil Manchar Kamel Boufaa Nabil Chabour Abdeslam Demdoum Department of Applied Biology Universite des Freres Mentouri Constantine 1025000 ConstantineAlgeria Department of Geology Universite des Freres Mentouri Constantine 1025000 ConstantineAlgeria Laboratory of Geology and Environment (LGE) Uni versite des Freres Mentouri Constantine 1ConstantineAlgeria Department of Geology Sciences University of Larbi Ben M'hidi04000 Oum El BouaghiAlgeria Department of Earth Sciences University of Setif 119000 SetifAlgeria

A study of thirteen geothermal springs located in the geothermal field of Guelma,northeastern Algeria,was *** were collected during the period between January 2014 and February *** processes responsible for the chemical composition of thermal and mineralized water were *** hydrochemical analysis shows that the thermal waters are characterized by the presence of two different chemical facies,the first type SO4-Ca in the east,west and south of Guelma,the second type HCO3-Ca in the *** analysis also attributed to sodium,chlorides,and sulfates to an evaporitic terrigenous origin by the molar ratio Sr2+/Ca2+.The thermal spring waters from Guelma geothermal system have a meteoric origin,and all samples are immature with strong mixing between hot and shallow waters with 19-38.5%rate of *** silica geothermometer shows that these thermal waters have a temperature varying from 84 to 122℃and that the water came from a depth of 2100-3000 m through a fault system that limits the pullapart basin of *** environmental effluent from thermal spas could pollute in both the irrigation and drinking waters,and which imposes danger on the health of the inhabitants of the region.

关键词： Geochemistry Geothermometry Mixing Thermal effluents Guelma Algeria

Wearing resistance of in-situ Al-based composites with different SiO_2/C/Al molar ratios fabricated by reaction hot pressing

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Transactions of Nonferrous Metals Society of China 2016年第4期26卷 917-923页

作者： El oualid MOKHNACHE 王桂松耿林哈尔滨工业大学材料科学与工程学院哈尔滨150001

The in-situ Al-based composites with different SiO2/C/Al molar ratios were fabricated by reaction hot pressing. The dry sliding wear characteristics of the composites were investigated using a pin-on-disc wear tester. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to investigate the surface composition and its morphology. The results show that when the SiO2/C/Al molar ratio is 3:6:9, more in-situ synthesized Al2O3 and SiC along with Si particles are produced, and Al4C3 is prevented completely from the Al?SiO2?C system. Thereby, a significant improvement of wear resistance is obtained. When the sliding velocity increases from 0.4 to 1.6 m/s, the wear loss decreases gradually. With increasing the normal load, the wear loss increases as well. Ploughing, craters and micro-grooving are observed as dominant abrasive wear mechanisms. Whereas, when a high velocity is employed, only the oxidation mechanism controls the wear behavior of the composites.

关键词： metal matrix composite wear mechanism friction hardness

Strategic and Organizational Evolutions of High-Tech SME on Global Market

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Chinese Business Review 2011年第5期10卷 327-339页

作者： oualid Abidi Zhan Su Muhammad Mohiuddin Laval University Quebec Canadian

The ＂OLI paradigm＂ of Dunning （1977） claims that firm internationalization is addressed toward the exploitation of home-based specific advantages. However, evidence shows that SMEs are increasingly internationalizing their activities in order to enrich their resource pool. In this regard, a reinterpretation of the OLI paradigm came out with a new perspective suggesting that ＂foreign direct investmenf＇（FDI） is increasingly oriented toward asset augmentation. Correspondingly, the purpose of this theoretical paper is to suggest a set of principles that could inform on how global small and medium-sized enterprises grow in the international marketplace when investing abroad.

关键词： SME OLI knowledge exploitation exploration

Stability Study of the Metrological Characteristics of a ZnO/PS/C-Si Photodiode (PSiZ) Used as a Transfer

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Modern Instrumentation 2012年第2期1卷 21-25页

作者： Zahra Ben Achour oualid Touayar Nejmeddine Sifi Institut National des Sciences Appliquées et de Technologie (INSAT) University of Carthage Laboratoire Matériaux Mesures et Applications (MMA) Groupe de Recherche en Métrologie des Rayonnements Tunis Tunisia University of Carthage Tunis Tunisia

This paper presents the results of a stability study of a photodiode realized in the Laboratoire de Métrologie des Rayonnements (LMR-INSAT, Tunisia). The study was performed during six years and concerned with the photodiode optical and electrical characteristics. This study involves in one side, the reflectivity stability for different wavelengths and in the other side, the stability of the series and shunt resistances. The experimental results confirm the stability of the photodiode spectral response since the reflection coefficient maximum uncertainty is equal to 0.0055 with an experimental uncertainty of about 0.0016 (at 1? level) for the mean value of the reflectivity over the study duration. Moreover, the shunt and series resistances are equal to 5.14 k? and 7.61 ? respectively with an uncertainty value of 0.01 k? and 0.04 ? respectively (at 1? level). This photodiode does not display any ageing aspect. Consequently, the PSiZ photodiode can be used as a Transfer Standard for radiometric measurement in the visible spectral range.

关键词： Photodiode Stability Transfer Standard Reflectivity Radiometric Measurements

A simple multi-wave algorithm for the uncapacitated facility location problem

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Frontiers of Engineering Management 2018年第4期5卷 451-465页

作者： Fred GLOVER Said HANAFI oualid GUEMRI Igor CREVITS Leeds School of Business University of ColoradoBoulderCO 80309-0419USA LAMIH CNRS UMR 8201Université de ValenciennesFrance

The multi-wave algorithm(Glover, 2016)integrates tabu search and strategic oscillation utilizing repeated waves(nested iterations) of constructive search or neighborhood search. We propose a simple multi-wave algorithm for solving the Uncapacitated Facility Location Problem(UFLP) to minimize the combined costs of selecting facilities to be opened and of assigning each customer to an opened facility in order to meet the customers' demands. The objective is to minimize the overall cost including the costs of opening facilities and the costs of allocations. Our experimental tests on a standard set of benchmarks for this widely-studied class of problems show that our algorithm outperforms all previous methods.

关键词： discrete optimization UFLP multi-wave optimization strategic oscillation tabu search