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Evaluation of adsorption capacities of humic acids extracted from Algerian soil on polyaniline for application to remove pollutants such as Cd(Ⅱ), Zn(Ⅱ) and Ni(Ⅱ) and characterization with cavity microelectrode

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Journal of Environmental Sciences 2011年第7期23卷 1095-1103页

作者： achour terbouche Chafia Ait Ramdane-terbouche Didier Hauchard Safia Djebbar Center of Scientific Research and Technical in Physical and Chemical Analysis Laboratory of Hydrometallurgy and Molecular Inorganic Chemistry Faculty of Chemistry University of Sciences and Technology Houari Boumediene Sciences Chimiques de Rennes UMR CNRS 6226 Ecole Nationale Supe'rieure de Chimie de Rennes avenue du ge'ne'ral Leclerc Universite' Europe'enne de Bretagne 12 Avenue Janvier 35000 Rennes France

The adsorption capacities of new humic acids isolated from Yakouren forest （YHA） and Sahara （Tamenrasset： THA） soils （Algeria） and commercial humic acid （PFHA） on polyaniline emeraldine base （PEB） were studied at pH 6.6. Also the adsorption of heavy metals such as Cd 2＋ , Zn 2＋ and Ni 2＋ on humic acid-polyaniline systems （HA-PEB） was investigated at the same conditions. HA-PEB compounds were characterized by scanning electron microscopy （SEM）, infrared spectrometry and cavity microelectrode. In addition, batch adsorption and cavity microelectrode were used in the adsorption study of Cd 2＋ , Zn 2＋ and Ni 2＋ on HA-PEB. To develop biocaptors of polluting metals using a cavity microelectrode modified by HA-PEB systems, the adsorption kinetic and adsorption capacity were investigated. The SEM analysis showed that the presence of humic acid affected the PEB surface and caused the formation of a granular morphology. The maximum adsorption capacities （q max ） of PFHA, THA and YHA determined by adsorption isotherms were 91.31, 132.1 and 151.0 mg/g, respectively. Batch adsorption results showed that q max of Cd 2＋ , Zn 2＋ and Ni 2＋ on HA-PEB followed the order： THA-PEB YHA-PEB PFHA-PEB. The voltammograms obtained with HA-PEB modified cavity microelectrode showed the appearance of new redox couples reflecting the adsorption of HA on PEB. Metal-humic acid-polyaniline voltammograms were characterized by appearance of oxidation-reduction couples or reduction wave corresponding to metal. Finally, the result may be exploited to develop a biocaptor based on the cavity microelectrode amended by THA-PEB and YHA-PEB.

关键词： adsorption capacity forest and Sahara humic acids polyaniline heavy metal modified cavity microelectrode.

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Modelling the spatial distribution of snake species in northwestern Tunisia using maximum entropy(Maxent) and Geographic Information System(GIS)

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Journal of Forestry Research 2018年第1期29卷 233-245页

作者： Mohsen Kalboussi Hammadi achour Institut Sylvo-pastoral de Tabarka Universit6 de Jendouba8110 Tabarka Tunisia Unite de recherche 《Geomatique des Geosystemes》 02/UR/10-01 Universite de la Mannouba Campus universitaire B.P. 95 2010 Mannouba Tunisia

We used GIS and maximum entropy to predict the potential distribution of six snake species belong to three families in Kroumiria（Northwestern Tunisia）： Natricidae（Natrix maura and Natrix astreptophora）, Colubridae（Hemorrhois hippocrepis, Coronella girondica and Macroprotodon mauritanicus）, and Lamprophiidae（Malpolon insignitus）. The suitable habitat for each species was modelled using the maximum entropy algorithm, combining presence field data（collected during 16 years：2000–2015） with a set of seven environmental variables（mean annual precipitation, elevation, slope gradient,aspect, distance to watercourses, land surface temperature and normalized Differential Vegetation Index. The relative importance of these environmental variables was evaluated by jackknife tests and the predictive power of our models was assessed using the area under the receiver operating characteristic. The main explicative variables of the species distribution were distance from streams and elevation, with contributions ranging from 60 to 77 and from 10 to 25%,respectively. Our study provided the first habitat suitability models for snakes in Kroumiria and this information can be used by conservation biologists and land managers concerned with preserving snakes in Kroumiria.

关键词： Species distribution modelling Maxent Snakes Kroumiria Tunisia

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How do machine learning techniques help in increasing accuracy of landslide susceptibility maps?

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Geoscience Frontiers 2020年第3期11卷 871-883页

作者： Yacine achour Hamid Reza Pourghasemi Department of Civil Engineering Bordj Bou Arreridj University34030El AnnasserAlgeria Department of Natural Resources and Environmental Engineering College of AgricultureShiraz UniversityShirazIran

Landslides are abundant in mountainous *** are responsible for substantial damages and losses in those *** A1 Highway,which is an important road in Algeria,was sometimes constructed in mountainous and/or semi-mountainous *** studies of landslide susceptibility mapping conducted near this road using statistical and expert methods have yielded ordinary *** this research,we are interested in how do machine learning techniques help in increasing accuracy of landslide susceptibility maps in the vicinity of the A1 Highway *** do this,an important section at Ain Bouziane(NE,Algeria) is chosen as a case study to evaluate the landslide susceptibility using three different machine learning methods,namely,random forest(RF),support vector machine(SVM),and boosted regression tree(BRT).First,an inventory map and nine input factors were prepared for landslide susceptibility mapping(LSM) *** three models were constructed to find the most susceptible areas to this *** results were assessed by calculating the receiver operating characteristic(ROC) curve,the standard error(***),and the confidence interval(CI) at 95%.The RF model reached the highest predictive accuracy(AUC=97.2%) comparatively to the other *** outcomes of this research proved that the obtained machine learning models had the ability to predict future landslide locations in this important road *** addition,their application gives an improvement of the accuracy of LSMs near the road *** machine learning models may become an important prediction tool that will identify landslide alleviation actions.

关键词： Spatial modelling Support vector machine Random forest Boosted regression tree Validation measures Algeria

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Synthesis of glass ceramics from kaolin and dolomite mixture

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International Journal of Minerals,Metallurgy and Materials 2017年第2期24卷 194-201页

作者： Mohamed Reda Boudchicha Fausto Rubio Slimane achour Engineering Mechanics and Materials Laboratory Mechanical Engineering Department Faculty of Technology Universite 20 Aout 1955 de Skikda Skikda 21000 Algeria Ceramics and Glass Institute Consejo Superior de Investigaciones Cientificas Madrid 28049 Spain National Polytechnic School Constantine 25000 Algeria

Cordierite- and anorthite-based binary glass ceramics of the CaO-MgO-Al2O3-SiO2 （CMAS） system were synthesized by mixing local and abundant raw minerals （kaolin and doloma by mass ratio of 82/18）. A kinetics study reveals that the activation energy of crystalli- zation （Ea） calculated by the methods of Kissinger and Marotta are 438 kJ·mol^-1 and 459 kJ·mol^-1, respectively. The Avrami parameter （n） is estimated to be approximately equal to 1, corresponding to the surface crystallization mechanism. X-ray diffraction （XRD） analysis shows that the anorthite and cordierite crystals are precipitated from the parent glass as major phases. Anorthite crystals first form at 850℃, whereas the μ-cordierite phase appears after heat treatment at 950℃. Thereafter, the cordierite allotropically transforms to α-cordierite at 1000℃. Complete densification is achieved at 950℃; however, the density slightly decreases at higher temperatures, reaching a stable value of 2.63 kg·m^-3 between 1000℃ and 1100℃, The highest Vickers hardness of 6 GPa is also obtained at 950℃. However, a substantial decrease in hardness is recorded at 1000℃; at higher sintering temperatures, it slightly increases with increasing temperature as the ct-cordierite crystallizes.

关键词： glass ceramics kaolinite dolomite crystallization activation energy

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Preparation of n-type semiconductor SnO_2 thin films

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Journal of Semiconductors 2013年第8期34卷 25-28页

作者： achour Rahal Said Benramache Boubaker Benhaoua VTRS Laboratory Institute of TechnologyUniversity of El-oued 39000Algeria Physics Laboratory Institute of TechnologyUniversity of El-oued 39000Algeria Material Sciences Laboratory Faculty of ScienceUniversity of Biskra 07000Algeria

We studied fluorine-doped tin oxide on a glass substrate at 350℃using an ultrasonic spray technique. Tin（Ⅱ） chloride dehydrate,ammonium fluoride dehydrate,ethanol and NaOH were used as the starting material, dopant source,solvent and stabilizer,*** SnO_2：F thin films were deposited at 350℃and a pending time of 60 and 90 *** as-grown films exhibit a hexagonal wurtzite structure and have（101） *** G = 31.82 nm value of the grain size is attained from SnO_2：F film grown at 90 s,and the transmittance is greater than 80%in the visible *** optical gap energy is found to measure 4.05 eV for the film prepared at 90 s, and the increase in the electrical conductivity of the film with the temperature of the sample is up to a maximum value of 265.58（Ω·cm）^（-1）,with the maximum activation energy value of the films being found to measure 22.85 meV,indicating that the films exhibit an n-type semiconducting nature.

关键词： SnO_2:F thin film TCO ultrasonic spray technique

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The effect of the film thickness and doping content of SnO2:F thin films prepared by the ultrasonic spray method

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Journal of Semiconductors 2013年第9期34卷 21-25页

This paper reports on the effects of film thickness and doping content on the optical and electrical properties of fluorine-doped tin oxide. Tin （Ⅱ） chloride dehydrate, ammonium fluoride dehydrate, ethanol and HC1 were used as the starting materials, dopant source, solvent and stabilizer, respectively. The doped films were deposited on a glass substrate at different concentrations varying between 0 and 5 wt% using an ultrasonic spray technique. The SnO2：F thin films were deposited at a 350 ℃ pending time （5, 15, 60 and 90 s）. The average transmission was about 80%, and the films were thus transparent in the visible region. The optical energy gap of the doped films with 2.5 wt% F was found to increase from 3.47 to 3.89 eV with increasing film thickness, and increased after doping at 5 wt%. The decrease in the Urbach energy of the SnO2：F thin films indicated a decrease in the defects. The increase in the electrical conductivity of the films reached maximum values of 278.9 and 281.9 （Ω.cm）-1 for 2.5 and 5 wt% F, respectively, indicating that the films exhibited an n-type semiconducting nature. A systematic study on the influence of film thickness and doping content on the properties of SnO2：F thin films deposited by ultrasonic spray was reported.

关键词： SnO2 fluoride thin film film thickness TCO ultrasonic spray technique

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Inhomogeneous barrier height effect on the current–voltage characteristics of an Au/n-InP Schottky diode

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Journal of Semiconductors 2015年第12期36卷 81-86页

作者： Kamal Zeghdar Lakhdar Dehimi achour Saadoune Nouredine Sengouga Laboratory of Metallic and Semi-conducting Materials (LMSM) Université de Biskra Faculty of Science Université de Batna

We report the current-voltage （I-V） characteristics of the Schottky diode （Au/n-InP） as a function of temperature. The SILVACO-TCAD numerical simulator is used to calculate the I-V characteristic in the tem- perature range of 280-400 K. This is to study the effect of temperature on the I-V curves and assess the main parameters that characterize the Schottky diode such as the ideality factor, the height of the barrier and the series resistance. The I-V characteristics are analyzed on the basis of standard thermionic emission （TE） theory and the inhomogeneous barrier heights （BHs） assuming a Gaussian distribution. It is shown that the ideality factor de- creases while the barrier height increases with increasing temperature, on the basis of TE theory. Furthermore, the homogeneous BH value of approximately 0.524 eV for the device has been obtained from the linear relationship between the temperature-dependent experimentally effective BHs and ideality factors. The modified Richardson plot, according to the inhomogeneity of the BHs, has a good linearity over the temperature range. The evaluated Richardson constant A^＊ was 10.32 A·cm^-2·K^-2, which is close to the theoretical value of 9.4 A·cm^-2·K^-2 for nInP. The temperature dependence of the I-V characteristics of the Au/n-InP Schottky diode have been successfully explained on the basis of the thermionic emission （TE） mechanism with a Gaussian distribution of the Schottky barrier heights （SBHs）. Simulated I-V characteristics are in good agreement with the measurements [Korucu D, Mammadov T S. J Optoelectronics Advanced Materials, 2012, 14：41 ]. The barrier height obtained using Gaussian Schottky barrier distribution is 0.52 eV, which is about half the band gap of InP.

关键词： simulation SDB Silvaco InP temperature I-V-T

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Corrosion behaviour and cytocompatibility of selected binary magnesium-rare earth alloys

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Journal of Magnesium and Alloys 2021年第2期9卷 581-591页

作者： Hiba Azzeddine Abdelkader Hanna achour Dakhouche Bérengère Luthringer-Feyerabend Department of Physics Faculty of SciencesUniversity of Mohamed BoudiafM’silaAlgeria Inorganic Materials Laboratory Department of ChemistryFaculty of SciencesUniversity of Mohamed BoudiafM’silaAlgeria Metallic Biomaterials Institute of Material ResearchHelmholtz-Zentrum Geesthacht21502 GeesthachtGermany

The corrosion behaviour of as-cast binary Mg–0.3 Ce,Mg–1.44 Nd,Mg–0.63 Gd and Mg–0.41 Dy(wt%)alloys was investigated in DMEM+10%FBS solution using electrochemical and weight loss *** results revealed that the alloys with heavy RE elements(Gd and Dy)exhibited the lowest corrosion rate compared to the alloys with light RE elements(Ce and Nd).The cytocompatibility of the Mg–RE alloys was assessed via live/dead straining after 3 and 7 *** results show that Mg–0.63 Gd alloy is a suitable candidate for biomedical applications.

关键词： Corrosion Cytotoxicity Magnesium alloys Rare earth element Weight loss test

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Electrodes based on nano-tree-like vanadium nitride and carbon nanotubes for micro-supercapacitors

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Journal of Materials Science & Technology 2018年第6期34卷 976-982页

作者： Nadir Ouldhamadouche Amine achour Raul Lucio-Porto Mohammad Islam Shahram Solayman Ali Arman Azin Ahmadpourian Hamed achour Laurent Le Bri-zoual Mohamed Abdou Djouadi Thierry Brousse Laboratoire de Génie Physique Université lbn Khaldoun BP P 78 Zaaroura 14000 Tiaret Algeria National Institute of Scientific Research 1650 Bd. Lionel-Boulet Varennes QCJ3X1P7 Canada Universidad Autónoma de Nuevo León Facultad de lngeniería Mecdnica y Eléctrica San Nicolas de los Garza 66450 Nuevo León Mexico Universidad Autónoma de Nuevo León Centro de lnnovación Investigación y Desarrollo en lngeniería y Tecnología Apodaca 66600 Nuevo León Mexico Deanship of Scientific Research Advanced Manufacturing Institute King Saud University P.O. Box 800 Riyadh 11421 Saucli Arabia Department of Physics Science and Research Branch Islamic Azad University Tehran Iran Vacuum Technology Group ACECR Sharif Branch Tehrun Iran Young Researchers and Elite Club Arak Branch Islamic Azad University Arak Iran Institute of Condensed Matter Physics Ecole Polytechnique Fédérale de Lausanne (EPFL) CH-1015 Lausanne Switzerland University of Rennes 1 Institut d'Electronique et de Télécommunications IETR - UMR CNRS 6164 Campus de Beaulieu -Bat 11D 263 Av General Leclerc 35042 Rennes cedex France Institut des MateriauxJean Rouxel (IMN) Universite de Nantes CNRS 2 rue de la Houssiniere BP32229 44322 Nantes Cedex 3 France Reseau sur le Stockage Electrochimique de l'Energie (RS2E) FR CNRS 3459 France

Vanadium nitride （VN） was deposited by DC-sputtering on a vertically aligned carbon nanotube （CNTs） template for the purpose of nano-structuration. This led to the fabrication of hierarchically composite electrodes consisting of porous and nanostructured VN grown on vertically aligned CNTs in a nano-treelike configuration for micro-supercapacitor application. The electrodes show excellent performance with an areal capacitance as high as 37.5 mF cm^-2 at a scan rate of 2 mV s^-1 in a 0.5 M K2504 mild electrolyte solution. Furthermore, the capacitance decay was only 15% after 20,000 consecutive cycles. Moreover, the capacitance was found to increase with VN deposit thickness. The X-ray photoelectron spectroscopy analyses of the electrodes before and after cycling suggest that the oxide layers that form at the VN surface is the responsible for the redox energy storage in this material. Such electrodes can compete with other transition metal nitride based electrodes for micro-supercapacitors.

关键词： Vanadium nitride CNTs Micro-supercapacitors Surface chemistry

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Smart model for accurate estimation of solar radiation

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Frontiers in Energy 2020年第2期14卷 383-399页

作者： Lazhar achour Malek BOUHARKAT Ouarda ASSAS Omar BEHAR Electrical Engineering Department University of Batna 2Fesdis 05110Algeria Laboratory Pure and Applied Mathematics(LPAM) University of M’silaM’sila 28000Algeria University of M’Hammed Bougara UMBBBoumerdes 35000Algeria

Prediction of solar radiation has drawn increasing attention in the recent *** is because of the lack of solar radiation measurement *** the present work,14 solar radiation models have been used to assess monthly global solar radiation on a horizontal surface as function of three parameters:extraterrestrial solar irradiance(),duration sunshine()and daylight hours().Since it has been observed that each model is adequate for some months of the year,one model cannot be used for the prediction of the whole ***,a smart hybrid system is proposed which selects,based on the intelligent rules,the most suitable prediction model of the 14 models listed in this *** the test and evaluation of the proposed models,Tamanrasset city,which is located in the south of Algeria,is selected for this *** meteorological data sets of five years(2000–2004)have been collected from the Algerian National Office of Meteorology(NOM),and two spatial *** results indicate that the new hybrid model is capable of predicting the monthly global solar radiation,which offers an excellent measuring accuracy of values ranging from 93%to 97%in this location.

关键词： global solar radiation statistical indicator hybrid model spatial database correlation coefficients

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