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Development of Molybdenum Trioxide （MoO3） by Spin Coating Method for Photovoltaic Application

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材料科学与工程（中英文B版） 2013年第7期3卷 418-422页

作者： Loundja Chibane Mohamed Said Belkaid Marcel Pasquinelli hassina derbal-habak Jean-Jacque Simon Dallila Hocine Laboratory of Advanced Technologies of Genie Electrics (LATAGE) Faculty of Electrical and Computer Engineering MouloudMammeri University (UMMTO) Tizi-Ouzou BP 17 RP 15000 Algeria Institute for Microelectronics Materials Nanosciences of Provence (1M2NP) Aix-Marseille University Marseille Cedex 20F-13397 France

Molybdenum trioxide (MoO3), thin films have been deposited on glass substrates by spin-coating method using ammonium heptamolybdate tetrahydrate ((NH4)6Mo7O24·4H2O ) as a single source precursor of Mo and O. They were subjected to atmospheric heat treatment at different temperatures (200, 400 and 500 °C). MoO3 thin films obtained were characterized using X-ray diffraction techniques (XRD), scanning electron microscopy (SEM), energy dispersed spectroscopy (EDS) and integrating sphere. The XRD patterns of annealed films show the formation of ΜοΟ3 in a polycrystalline phase, formation of MoO3 was also confirmed by EDS. The SEM photographs show that the thin films obtained are in layer-type structure and their grains size increases with increasing of annealing temperatures. The measurement results of integrating sphere show that the MoO3 thin film prepared at 500 °C transmit about 72% and reflect about 12% of the visible spectrum.

关键词：三氧化钼薄膜旋转涂布法 X射线衍射技术扫描电子显微镜应用光伏退火温度七钼酸铵

Remote Sensing and Landscape Metrics-Based Forest Physical Degradation: Two-Decades Assessment in Gishwati-Mukura Biological Corridor in Rwanda, East-Central Africa

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Journal of Geoscience and Environment Protection 2022年第4期10卷 64-81页

作者： hassina Uwiringiyimana Jaeyong Choi Department of Environment and Forest Resources Chungnam National University Daejeon Republic of Korea

The management of forest corridors and related ecology is one of the effective strategies to minimize the adverse effects of forest degradation. It controls the connectivity of inhabitant species and the connection of the isolated patches. This study analyzed spatial and temporal forest physical degradation based on forest cover change and forest fragmentation in the Gishwati-Mukura biological corridor from 1990-2019. Remotely sensed datasets, Geographical Information System (GIS) and FRAGSTATS software were used to analyze the spatial and temporal physical degradation and changes in forest cover. The results indicated that the Gishwati-Mukura corridor experienced massive deforestation where approximately 7617.1 ha (64.22%) of forest cover was completely cleared out, which implies an annual forest loss of 262.6 ha·year-1 (2.21%) during 1990-2019. The forest cover transitions patterns and geostatistical analysis indicated that extensive deforestation was associated with intensive agriculture. The results demonstrated that agriculture has dramatically increased from 29.46% in 1990 to 57.22% in 2019, with an annual increase of 1.97%. Since Gishwati-Mukura has changed to National Park (NP), it lacks diversified scientific studies addressing the analysis of the remote and spatial patterns to investigate its physical degradation and landscape dynamics. This research study will serve as remote forest analysis gap-filling and as the cornerstone of numerous other research that will contribute to the improvement of the connectivity assessments along the Gishwati-Mukura corridor and other related ecosystems.

关键词： Landscape Metrics Remote Sensing Geographic Information System (GIS) Forest Physical Degradation Biological Corridor National Park

Atomic Fe-N4 sites on electrospun hierarchical porous carbon nanofibers as an efficient electrocatalyst for oxygen reduction reaction

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Chinese Chemical Letters 2020年第6期31卷 1588-1592页

作者： Ruiqin Zhong Chenxu Zhi Yingxiao Wu Zibin Liang hassina Tabassum Hao Zhang Tianjie Qiu Song Gao Jinming Shi Ruqiang Zou State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials Department of Materials Science and EngineeringCollege of EngineeringPeking UniversityBeijing J00871China

Porous carbon materials doped with atomically dispersed metal sites(ADMSs)are promising electrocatalysts for oxygen reduction reaction(ORR)*** this work,we fabricated hierarchical porous nitrogen-doped carbon nanofibers with atomically dispersed Fe-N4 sites by carbonization of electrospinning iron-based metal-organic frameworks(MOFs)/polyacrylonitrile nanofibers for ORR ***,the re sultant carbon nanofibers with atomically dispersed FeN4 sites exhibit extraordinary electrochemical performance with an onset potential of 0.994 V and a halfwave potential of 0.876 V in alkaline electrolyte,comparable to the benchmark commercial Pt/C *** high catalytic performance is originated from the unique hierarchically porous 1 D carbon structure and abundant highly active atomically dispersed Fe-N4 sites.

关键词： Atomically dispersed metal sites Metal-organic frameworks Electrospinning Oxygen reduction reaction Electrocatalysis

Requirement-driven Architecture for Learning Analytics:The Case of AT41 Project

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计算机教育 2021年第12期 201-209页

作者： Nesrine Zibani Ladjel Bellatreche hassina El Kechai Sébastien Iksal with LIAS ISAE-ENSMAPoitiers86000France Techne Poitiers UniversityPoitiers86000France LIUM University of Le MansLaval53000France

Digital technologies are becoming present and essential in all sectors of our *** education,the intensive usage of digital learning devices contributes to generating a large amount of trace data from digital learning *** exploitation of these traces represents a valuable asset for both device producers(to improve the design of the devices)and consumers(learners and teachers).In this paper,we first share our vision for better exploitation by teachers,of traces from middle schoolers’digital activities generated by their use of tools and digital learning services during different *** vision is a part of the AT41 project funded by the French Ministry of *** exploitation has to meet the requirements of the different *** such a project is not an easy task,because it has to consider the following issues:①the lack of comprehensive and clear methodology to design and exploit these traces;①heterogeneity of teacher requirements that complicates their elicitation and analysis;①the diversity of trace ***,we propose a requirement-driven architecture for Learning Analytics composed of a well-identified life *** architecture is augmented by learner *** offers a repository storing both teacher requirements and traces to facilitate the Learning Analytics in generating relevant and valuable indicators.

关键词： dashboard learning analytics trace exploitation requirements

Time Domain Modeling of Powerline Impulsive Noise at Its Source

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Journal of Electromagnetic Analysis and Applications 2011年第9期3卷 359-367页

作者： hassina Chaouche Frederic Gauthier Ahmed Zeddam Mohamed Tlich Mohamed Machmoum 不详

Noise characteristics of an indoor power line network strongly influence the link capability to achieve high data rates. The appliances shared with PLC modems in the same powerline network generate different types of noises, among them the impulsive noises are the main source of interference resulting in signal distortions and bit errors during data transmission. With regard to impulsive noise many models were proposed in the literature and shared the same impulsive noise definition: “unpredictable noises measured in the receiver side”. Authors are, consequently, confronted to model thousands of impulsive noises whose plurality would very likely come from the diversity of paths that the original impulsive noise took. In this paper, an innovative modelling approach is applied to impulsive noises which are studied here directly at their sources. Noise at receiver would be simply the noise model at source convolved by powerline channel block. In the new analytical model, the impulsive noise at source is described by a succession of short pulses, each modeled by a phase-shifted Gaussian. Noises at source are classified into 6 different classes [1], and a noise generator is established for each class.

关键词： Powerline Communication Impulsive Noise Modeling Electrical Appliances

Spontaneous Imbibition of Water and Determination of Effective Contact Angles in the Eagle Ford Shale Formation Using Neutron Imaging

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Journal of Earth Science 2017年第5期28卷 874-887页

作者： Victoria H.DiStefano Michael C.Cheshire Joanna McFarlane Lindsay M.Kolbus Richard E.Hale Edmund Perfect hassina Z.Bilheux Louis J.Santodonato Daniel S.Hussey David L.Jacobson Jacob M.LaManna Philip R.Bingham Vitaliy Starchenko Lawrence M.Anovitz Physical Sciences Directorate Chemical Sciences Division Oak Ridge National Laboratory Bredesen Center University of Tennessee Energy & Environmental Sciences Directorate Energy & Transportation Sciences Division Oak Ridge National Laboratory Neutron Sciences Directorate Chemical and Engineering Materials Division Oak Ridge National Laboratory Nuclear Science & Engineering Directorate Reactor & Nuclear Systems Division Oak Ridge National Laboratory Department of Earth and Planetary Science University of Tennessee Neutron Sciences Directorate Instrument and Source Division Oak Ridge National Laboratory Physical Measurement Laboratory National Institute of Standards and Technology Energy & Environmental Sciences Directorate Electrical & Electronics Systems Research DivisionOak Ridge National Laboratory

Understanding of fundamental processes and prediction of optimal parameters during the horizontal drilling and hydraulic fracturing process results in economically effective improvement of oil and natural gas extraction. Although modern analytical and computational models can capture fracture growth, there is a lack of experimental data on spontaneous imbibition and wettability in oil and gas reservoirs for the validation of further model development. In this work, we used neutron im- aging to measure the spontaneous imbibition of water into fractures of Eagle Ford shale with known geometries and fracture orientations. An analytical solution for a set of nonlinear second-order diffe- rential equations was applied to the measured imbibition data to determine effective contact angles. The analytical solution fit the measured imbibition data reasonably well and determined effective con- tact angles that were slightly higher than static contact angles due to effects of in-situ changes in veloci- ty, surface roughness, and heterogeneity of mineral surfaces on the fracture surface. Additionally, small fracture widths may have retarded imbibition and affected model fits, which suggests that aver- age fracture widths are not satisfactory for modeling imbibition in natural systems.

关键词： spontaneous imbibition effective contact angle neutron imaging Eagle Ford shale rock fractures.