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Application of Remote Sensing and GIS in Mineral Alteration Mapping and Lineament Extraction Case of Oudiane Elkharoub (Requibat Shield, Northern of Mauritania)

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Open Journal of Geology 2024年第9期14卷 823-854页

作者： Ould Mahmoud Hdeid Yousra Morsli Mohamed Raji Zouhir Baroudi Malika Adjour khaled Cheikh Nebagha Zein El Arby Vetah Mohamed El Moktar Isselmou Brahim Vall Department of Geology Faculty of Sciences Ben Msik Hassan II University Casablanca Morocco Department of Geology Faculty of Sciences and Technology University of Nouakchott Al Asriya Nouakchott Mauritania National Agency for Geological Research and Mining Heritage Nouakchott Mauritania

The integration of remotely sensed data allowed the successful characterization of the mineral alteration zones of the Oudiane Elkharoub area in the Northeastern part of Reguibat Shield using image transformation techniques. As both chemical and geochemical analyses showed significant Au, Ag, Cu, Pb, Mn, Cr, Ni, Th and Y anomalies, it’s very interesting to apply the remote sensing and GIS in mineral resources mapping. The remote sensing is a direct adjunct to the field, lithologic and structural mapping, and more recently, GIS has played an important role in the study of mineralization areas. The integration of several evidential maps highlighted the plausible areas with high concentrations of chlorite, epidote, kaolinite, calcite, alunite, hematite, illite and sulfur among other key mineral alterations that reflect the intensity of hydrothermal effects and the probable sites of ore bodies. The methodological approach integrates geological information acquired from Aster and Landsat 8 OLI/TIRS (Operational Land Imager/Thermal InfraRed Sensor) images and a multi-criteria GIS analysis. The superimposition of various lineament and hydrothermal alteration maps and the consideration of precious and base metal indicators allowed the zoning of sites likely to contain mineral concentrations. Remote sensing becomes an important tool for locating mineral deposits in its own right, when the primary and secondary processes of mineralization result in the formation of spectral anomalies. Reconnaissance lithological mapping is usually the first step of mineral resource mapping. This is complimented with structural mapping, as mineral deposits usually occur along or adjacent to geologic structures, and alteration mapping, as mineral deposits are commonly associated with hydrothermal alteration of the surrounding rocks. Ground truthing and laboratory studies including XRD analysis were utilized to verify the results.

关键词： Remote Sensing GIS ASTER Landsat 8 (OLI/TIRS) Structure Mineralization Alteration Mineral Lineament Reguibat Shield Oudiane Elkharoub

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Structural analysis by Rietveld refinement of calcium and lanthanum phosphosilicate apatites

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Journal of Rare Earths 2013年第9期31卷 897-904页

作者： Hela Njema khaled Boughzala Habib Boughzala khaled Bouzouita Laboratory of Industrial Chemistry National School of Engineering of Sfax Preparatory Institute for Engineering Studies of Monastir Laboratory of Materials and Crystallochemistry Preparatory Institute for Engineering Studies of Nabeul

Britholites with the general formula Ca10-xLnx（PO4）6-x（SiO4）xF2, （0≤x≤6） are considered to be promising matrices for the confinement of the by-products in the nuclear industry. A thermodynamic study showed that the stability of these compounds de-creased as the substitution rate increased. The present work was an attempt to gain more information about the structural changes in-duced by the substitution, in order to understand the observed stability decrease. The samples were successfully synthesized as a sin-gle-phase apatite by a solid-state reaction between 1200 and 1400 °C. The structural refinement indicated that the La3＋ions preferen-tially occupied the 6（h） sites. A progressive shift of F-along the c-axis outside its ideal position occurred as a result of the substitution increase. This might be the cause of the observed stability decrease, especially as the energies of the La-O, La-F and Si-O bonds are higher than those of Ca-O, Ca-F and P-O. The distribution of La3＋ between the two non-equivalent sites was confirmed by the charge distribution method.

关键词： britholites Rietveld refinement infrared spectroscopy charge distribution method rare earths

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Optimization and Simulation of Operation Performance in Crushing Plants Using Fuzzy Modelling

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Journal of Systems Science and Systems Engineering 2019年第6期28卷 766-780页

作者： khaled Ali Abuhasel Mechanical Engineering Department College of EngineeringUniversity of BishaBisha 61922Saudi Arabia

This research includes optimization of aggregate production of the stone crushing plant using fuzzy *** investigation includes onsite aggregate testing and fuzzy logic *** modelling is a type of computerized reasoning used to simulate the real plant *** this work,a lot of agent degree information for crushers were reproduced using fuzzy *** logic was then used to shape the information after a crusher *** logic is created to improve the final product gradation for the *** for utilizing the created fuzzy model is sketched out and could be utilized as a part of a representative preparing program or for informative *** the tonnages anticipated by fuzzy,it is evident that the program does great in predicting the final product tonnage with an average of 13.7 % for just four samples.

关键词： Aggregate production crushing fuzzy modelling product tonnage

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Thermoluminescent response of gamma irradiated Na^(+)–Cu^(+) ionexchanged silicate glass in large dose range

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Nuclear Science and Techniques 2023年第5期34卷 22-32页

作者： Safa Toumi khaled Farah Laboratoire de Physico‑Chimie des Matériaux Département de PhysiqueFacultédes Sciences de MonastirUniversitéde MonastirMonastirTunisia Institut Supérieur du Transport et de la Logistique de Sousse Universitéde Sousse4023 SousseTunisia Laboratoire de Recherche en Energie et Matière Développement des Sciences Nucléaires(LR16CNSTN02)Centre National des Sciences et Technologies Nucléaires2020 Sidi‑ThabetTunisia

The introduction of metals into vitreous matrices is the origin of various interesting phenomena;in particular,the presence of copper ions in glass has been the subject of considerable research because of its numerous *** ion-exchange process is primarily used to introduce copper ions into glass *** thermoluminescence(TL)of silicate glass was studied to evaluate its potential as gamma-sensitive material for dosimetric applications;the effect of copper doping on the thermoluminescent sensitivity was investigated using the Cu-Na ion-exchange technique for different concentrations and doping conditions,over a wide dose range of 10 mGy to 100 *** results showed that Cu doping significantly improved the sensitivity of the glasses to gamma *** the ion-exchange,two peaks appeared in the glow curves at approximately 175 and 230°C,respectively,which possibly originated from the Cu^(+) centers,along with a weak TL peak at around 320℃.We also attempted to explain the origin of the observed thermoluminescence by exploiting the Electron paramagnetic resonance(EPR)*** results clearly show quenching of the TL emission with increasing copper *** present work indicates that the thermoluminescence response of these glasses to gamma rays can be reasonably measured in the range of 0.001-100 *** study also facilitates the understanding of the basic TL mechanism in this glass system.

关键词： Cu-Na ion-exchange Silicate glass Thermoluminescence Gamma irradiation Electron paramagnetic resonance

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Ab initio study of structural,electronic,thermo-elastic and optical properties of Pt3Zr intermetallic compound

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Chinese Physics B 2020年第4期29卷 405-414页

作者： Wahiba Metiri khaled Cheikh Departement de Physique Facultedes SciencesUniversite 20 aout 1955-Skikda BP 26Route El-Hadaiek21000 SkikdaAlgeria Departement de Technologie Facultede TechnologieUniversite 20 aout 1955-Skikda BP 26Route El-Hadaiek21000 SkikdaAlgeria

Structural,elastic,electronic and optical properties of the Pt3Zr intermetallic compound are investigated using first principles calculations based on the density functional theory(DFT)within the generalized gradient approximation(GGA)and the local density approximation(LDA).The Pt3Zr compound is predicted to be of cubic L12 and hexagonal D024 *** calculated equilibrium ground-state properties(lattice parameters a and c,bulk modulus B and its pressure derivative B',formation enthalpy ΔH)of the Pt3Zr compound,for both cubic and hexagonal phases,show good agreement with the experimental results and other theoretical *** constants(C11,C12,C13,C33,C44,and C55)are *** predicted elastic properties such as Young's modulus E and shear modulus GH,Poisson ratioν,anisotropic ratio A,Kleinman parameter ξ,Cauchy pressure(C12-C44),ratios B/C44 and B/G,and Vickers hardness Hv indicate the stiffness,hardness and ductility of the *** characteristic parameters such as Debye temperature θD and melting temperature Tm are *** properties such as density of states(DOS)and electronic specific heat γ are also *** calculated results reveal that the Fermi level is on the psedogap for the D024 structure and on the antibonding side for the L12 *** optical property functions(real partε1(ω)and imaginary part ε2(ω)of dielectric function),optical conductivity σ(ω),refraction index n(ω),reflectivity R(ω),absorption α(ω)and extinction coefficients k(ω)and loss function L(ω)are also investigated for the first time for Pt3Zr in a large gamme of energy from 0 to 70 eV.

关键词： density functional theory intermetallic density of states L12 D024 optical properties

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Traditional farming in the mountainous region of Bangladesh and its modifications

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Journal of Mountain Science 2016年第8期13卷 1489-1502页

作者： MISBAHUZZAMAN khaled Institute of Forestry and Environmental Sciences Chittagong University

Shifting cultivation is a traditional farming system practiced in the tropical mountainous areas. Although it has been widely perceived as an economically inefficient and environmentally harmful agricultural production system, recent science reviews, however, indicate that the deleterious impacts of shifting cultivation on environment may have been overestimated. Despite the pressures of agricultural intensification in areas where shifting cultivation occurs, farmers across the tropics still maintain this traditional farming system. The objective of this study was to explore existing traditional shifting cultivation practices and their various modifications including the innovative farming techniques developed by farmers in the Chittagong Hill Tracts(CHTs), the mountainous region of Bangladesh, and examine their importance with respect to recent socio-economic and environmental changes. The study revealed that shifting cultivation still exists as the most dominant farming method which supports livelihoods and culture of the hill ethnic people. However, demand for more food and household income to meet livelihood needs of an increasing population combined with a rapid deterioration of soil and water quality over decades contributed to development of innovative farming practices through fallow land farming, crop substitution, agroforestry and homestead gardening in the CHTs. Through these farming techniques farmers maintain a strong relationship with traditional knowledge system embedded in the ageold shifting cultivation practices. Today state policies and market forces act in favor of replacement of traditional farming with intensive cash crop agriculture. It seems that disappearance of traditional farming practices from the hills may threaten local biodiversity and food security. It may be recommended that shifting cultivation should be encouraged in areas where they have potential for contributing to preservation of native biodiversity and ecosystem services, and

关键词： Shifting cultivation Chittagong HillTracts Agroforestry Food security

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Spatiotemporal variability/stability analysis of NO_(2),CO,and land surface temperature(LST)during COVID-19 lockdown in Amman city,Jordan

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Geo-Spatial Information Science 2023年第3期26卷 540-557页

作者： Ali Almagbile khaled Hazaymeh Department of Geography Applied Geoinformatics LaboratoryYarmouk UniversityIrbidJordan

The massive lockdown of human socioeconomic activities and vehicle movements due to the COVID-19 pandemic in 2020 has resulted in an unprecedented reduction in pollutant gases such as Nitrogen Dioxide(NO_(2))and Carbon Monoxide(CO)as well as Land Surface Temperature(LST)in Amman as well as all countries around the *** this study,the spatial and temporal variability/stability of NO_(2),CO,and LST throughout the lockdown period over Amman city have been *** NO_(2) and CO column density values were acquired from Sentinel-5p while the LST data were obtained from MODIS satellite during the lockdown period from 20 March to 24 April in 2019,2020,and *** statistical analysis showed an overall reduction in NO_(2) in 2020 by around 27% and 48% compared to 2019 and 2021,***,an increase of 7% in 2021 compared to 2019 was observed because almost all anthropogenic activities were allowed during the *** temporal persistence showed almost constant NO2 values in 2020 over the study area throughout the lockdown *** addition,a slight decrease in CO(around 1%)was recorded in 2020 and 2021 compared to the same period in *** on human activities resulted in an evident drop in LST in 2020 by around 13%and 18% less than the 5-year average and 2021 *** study concludes that due to the restrictions imposed on industrial activities and automobile movements in Amman city,an unprecedented reduction in NO_(2),CO,and LST was recorded.

关键词： Air quality COVID-19 lockdown spatiotemporal analysis NO_(2) CO Land Surface Temperature(LST) Sentinel-5p and MODIS satellites

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Spectroscopic studies and Rietveld refinement of strontium-britholites

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Journal of Rare Earths 2008年第4期26卷 483-489页

作者： khaled Boughzala Ezzedine Ben Salem Fethi Kooli Pierre Gravereau khaled Bouzouita U. R. Matériaux Inorganiques Institut Préparatoire aux Etudes d'Ingénieurs Rue Ibn ElJazzr 5019 Monastir Tunisia Department of Chemistry Taibah University P.O.Box 30002. Almadinah Almunawwarah Saudi Arabia 87 Avenue du Dr Schweitzer 33608 Pessac Cedex France

Strontium-britholites whose chemical formula was Sr10-xLax（PO4）6-x（SiO4）xF2, where x=0, 1, 2, and 4 were prepared by solid state reaction. The structural refinement carried out using the Rietveld method indicated that La^3＋ ions were located into the two sites with a strong preference for metal （2） sites especially for low contents. A progressive shift of the F position along the c-axis outside the centre of the triangle formed by metal （2）-atoms was observed with the increase of x. The infrared and Raman spectra exhibited the characteristic vibration modes of PO4 and SiO4groups confirming the incorporation of this last group into the apatite structure. The 295i MAS-NMR spectra exhibited one resonance peak confirming the data obtained by X-ray diffraction, indicating that P and Si were located in the same crystallographic site.

关键词： strontium brithofites Rietveld refinement infrared spectroscopy nuclear magnetic resonance (NMR) Raman spectroscopy rare earths

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Modeling severities of motorcycle crashes using random parameters

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第2期8卷 225-236页

作者： Ahmed Farid khaled Ksaibati Wyoming Technology Transfer Center Department of Civil and Architectural EngineeringUniversity of WyomingLaramieWY 82071USA

One of the critical areas of road safety is motorcycle safety. Motorcyclists are more vulnerable to injuries than occupants of other motor vehicles when involved in *** have studied the relationships between motorcycle crash severity and crash contributing factors. They are crash characteristics, roadway geometric design features,traffic characteristics, socio-demographics and environmental conditions. However, few researchers considered unobserved heterogeneity effects when modeling motorcycle crash injury severities, let alone interaction effects. In this research, motorcycle crashes in Wyoming that occurred from 2008 to 2017 were analyzed. Specifically, the injury severities of single motorcycle crashes and multiple vehicle crashes involving motorcycles were modeled. The response was whether the motorcycle crash incurred an incapacitating injury or fatality or not. The binary logistic regression and mixed binary logistic regression modeling structures were implemented. The mixed models revealed effects that otherwise would have been undisclosed in the binary logistic regression models’ results. According to the results of single motorcycle crashes, the majority of motorcycle-animal crashes and of motorcycle-barrier crashes were likely to be severe relative to other single motorcycle crashes. It was also found that horizontal curves increased the risk of severe *** riders were found to be less at risk of being gravely injured in single motorcycle crashes than older riders as well. Furthermore, riding under the influence and high posted speed limits increased the odds of severe crashes regardless of whether the crashes were single motorcycle crashes or multiple vehicle crashes involving motorcycles. Additionally,the mixed models uncovered interaction effects and unobserved effects pertaining to speed limits.

关键词： Transportation engineering Motorcycle safety Injury severity Logistic regression Random parameters

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Partial proportional odds model for analyzing pedestrian crashes,threshold heterogeneity by scale and proportional odds factor

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第6期9卷 969-977页

作者： Mahdi Rezapour khaled Ksaibati Wyoming Technology Transfer Center University of WyomingLaramieWY 82071USA

Despite low traffic in Wyoming,pedestrian crash severity accounts for a high number of fatalities in the *** this study was conducted to highlights factors contributing to those *** results highlighted that drivers under influence,type of vehicle,location of crashes,estimated speed of vehicles,driving over the recommended speed are some of factors contributing to the severity of *** this study,we used proportional odds model which assumes that the impact of each attribute is consistent or proportional across various threshold ***,it has been argued that this assumption might be unrealistic,especially at the presence of extreme ***,the assumption was relaxed in this study by shifting the thresholds based on some explanatory attributes,or proportional odds *** addition,we accounted for the spread rate,or scale,of the model’s latent distribution of pedestrian *** results highlighted that the partial proportional odds model through proportional odds factor and scale effects result in a significant improvement in model fit compared with the standard proportional odds *** were also made across standard normal,simple partial ordinal model,and partial ordinal accounting for scale *** addition,various potential threshold structures such as symmetric and flexible were considered,but similar goodness of fits were observed across all those *** discussion has been made regarding the formulation of the implemented methodology,and its implications.

关键词： Partial proportional odds model Pedestrian crashes Scale heterogeneity Proportional odds factor Vulnerable road users Drivers’lack of attention

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