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First-principles calculations to investigate structural,electronic,magnetic,optical and thermodynamic properties of RE_(2)Rh_(3)Ge(RE=Pr,Sm)

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Journal of Rare Earths 2024年第7期42卷 1385-1393,I0007页

作者： A.Ezaier R.Masrour M.Hamedoun J.Kharbach A.Rezzouk A.Hourmatallah N.Benzakour K.Bouslykhane laboratory of Solid Physics Faculty of Sciences Dhar El MehrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco Equipe de Physique du Solide LaboratoiresLIPIEcole Normale SupérieureBensoudaFèsMorocco

In this paper,we analyzed the physical characteristics of the ternary alloys RE_(2)Rh_(3)Ge(RE=Pr and Sm)using the first principles calculation based on functional density theory integrated in the Wien2k *** calculated formation energies of Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge are−5.3827 and−5.2782 eV/atom,respectively,showing that these alloys may exist *** results of the band structure and density of states indicate that all of the compounds tested are magnetic metals,and their magnetism is mostly related to the contribution of Pr and Sm *** total magnetic moments of Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge are 4.07245 and 11.16161μB/f.u,*** parameters such as heat capacity at constant pressure,entropy,debye temperature,lattice volume,compressibility coefficients,and Grüneisen parameter alloys were calculated using the Gibbs algorithm and studied in depth over a large temperature range of 0-900 *** debye temperature increases with increasing pressure and decreases with decreasing ***,the debye temperatures calculated at p=0 GPa and T=300 K are equal to be 342 and 322 K for Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge,*** optical characteristics such as the real and imaginary portions of the dielectric function,the absorption coefficient,the energy-loss function,and the refractive index were investigated and discussed in more depth.

关键词： Magnetic metals Functional density theory density of states Magnetic moment Optical and thermodynamic properties Rare earths

Dynamic of Scalar Bosons in Aharonov-Bohm Magnetic Field

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Journal of Applied Mathematics and Physics 2024年第1期12卷 268-276页

作者： Frédéric D. Y. Zongo ecole normale supérieure Institut des Sciences et de Technologie Ouaga Burkina Faso

We study the dynamic of scalar bosons in the presence of Aharonov-Bohm magnetic field. First, we give the differential equation that governs this dynamic. Secondly, we use variational techniques to show that the following Schrödinger-Newton equation: , where A is an Aharonov-Bohm magnetic potential, has a unique ground-state solution.

关键词： Scalar Boson Aharonov-Bohm Magnetic Field Schrödinger-Newton Equation Ground-State Solution

Petrographic and Geochemical Characteristics of the Pouni Palaeoproterozoic Formations North of the léo Square degree (Burkina Faso, West Africa)

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Open Journal of Geology 2024年第1期14卷 126-141页

作者： Adama Ouédraogo Yaméogo Pascal Ouiya Hubert Gounwendmanaghré Zongo Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta Naba Unité de Formation et de Recherche en Sciences et Technologies Département des Sciences de la Vie et de la Terre Université Norbert Zongo Koudougou Burkina Faso Unité de Formation et de Recherche en Sciences de la Vie et de la Terre Laboratoire Géosciences et Environnement (LaGE) Département des Sciences de la Terre Université Joseph Ki-Zerbo Ouaga Burkina Faso ecole normale supérieure (ENS) Institut des Sciences et de Technologie (IST) Ouaga Burkina Faso ecole supérieure d’Ingénieries Université de Fada N’gourma Fada N’Gourma Burkina Faso

The Pouni area is made up of basalts belonging to the Boromo belt, lamprophyres and granitoids. These geological formations are similar to geological formations of the same type in other regions of the Palaeoproterozoic domain of the Man/leo shield. This study, which focused on the petrographic and geochemical characteristics of these geological formations, led to the following main conclusions: The lamprophyres are basic plutonic rocks that cut through other geological formations. The basalt belongs to the northern part of the Borormo belt and is thought to be a relic of overthickened oceanic plateaus. There are two groups of granitoid rocks. The granodiorite has a geochemical signature close to that of Archean TTGs and is metaluminous in character. It has a low potassium content. The minor element and rare earth element spectra indicate that it could be derived from partial melting of basic magmatic rocks. Biotite granites are peraluminous and highly potassic. Minor element contents and rare earth spectra indicate that they could be derived from partial melting of felsic materials. Geotectonic diagrams show that the granitoids identified in the Pouni zone were emplaced in an active tectonic context, similar to that of present-day subduction zones.

关键词： Burkina Faso Dori Man/léo Shield Petrography Geochemistry Partial Melting Geotectonic Context

Insight from lithostructural and Aeromagnetic Data from the léo Square degree, Central-Western Burkina Faso

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Open Journal of Geology 2024年第1期14卷 19-28页

作者： Adama Ouédraogo Yaméogo Pascal Ouiya Gounwendmanaghré Hubert Zongo Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta Naba Unité de Formation et de Recherche en Sciences et Technologies Département des Sciences de la Vie et de la Terre Université Norbert Zongo Koudougou Burkina Faso Unité de Formation et de Recherche en Sciences de la Vie et de la Terre Laboratoire Géosciences et Environnement (LaGE) Département des Sciences de la Terre Université Joseph Ki-Zerbo Ouaga Burkina Faso ecole normale supérieure (ENS)/Institut des Sciences et de Technologie (IST) Ouaga Burkina Faso ecole supérieure d’Ingénieries Université de Fada N’gourma Fada N’Gourma Burkina Faso

This study, carried out in the léo square degree (west-central Burkina Faso) in the Palaeoproterozoic domain of the Man/léo ridge, aims to define the shapes and positions of granitic plutons and the organisation of deformation structures using aeromagnetic data. These data have shown that there are small sub-circular granitic bodies to the north of the granitic masses in this region, and a large sub-circular granitic body to the south, around which are other smaller granitic bodies. The lineament map shows that the deformation structures are organised along three main directions and largely form these sub-circular plutonic bodies. We suggest that the granitic plutons are coalescent, pending identification of the internal structures of these granites to further refine the geodynamic model.

关键词： Burkina Faso lineaments Belts Rocks leo’s leaf Granitoïd Airbornes Magnétics

Petrographic and Geochemical Characteristics of the Granitoids in the South of Godé (North of the Square degree of léo-Burkina Faso, West Africa)

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International Journal of Geosciences 2024年第2期15卷 106-118页

作者： Adama Ouédraogo Yaméogo Hubert Gounwendmanaghré Zongo Pascal Ouiya Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta Naba Unité de Formation et de Recherche en Sciences et Technologies Département des Sciences de la Vie et de la Terre Université Norbert Zongo Koudougou Burkina Faso Unité de Formation et de Recherche en Sciences de la Vie et de la Terre Laboratoire Géosciences et Environnement (LaGE) Départe-ment des Sciences de la Terre Université Joseph Ki-Zerbo Ouaga Burkina Faso ecole supérieure d’Ingénieries Université de Fada N’gourma Fada N’Gourma Burkina Faso ecole normale supérieure (ENS)/Institut des Sciences et de Technologie (IST) Ouaga Burkina Faso

South of Godé, in the central-western region of Burkina Faso, granitoids of Paleoproterozoic age are similar to those of the Man/leo shield. This study focused on the petrographic and geochemical characteristics of these granitoids, with the following results: 1) The tonalite that outcrops in the south-west of the study area belongs to the TTG group or first generation granitoids. They are most often ribboned at outcrop and have a geochemical signature close to that of Archean TTGs. Tonalite has a metaluminous character and the REE spectrum indicates that it may be derived from partial melting of basic magmatic rocks. 2) Biotite granites have no outcrop structure. They are weakly metaluminous to peraluminous and potassic to highly potassic. Their rare earth spectra indicate that they may be derived from the partial melting of TTG granitoids. 3) Geotectonic diagrams show that the granitoids studied to the south of Godé were emplaced in an active tectonic context similar to that of present-day subduction zones.

关键词： Burkina Faso Godé Man/leo Shield Petrography Geochemistry Partial Melting Geotectonic Setting

Micromechanism and mathematical model of stress sensitivity in tight reservoirs of binary granular medium

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Petroleum Science 2024年第3期21卷 1780-1795页

作者： Jian-Bang Wu Sheng-lai Yang Qiang li Kun Yang Can Huang Dao-Ping lv Wei Zhou State Key laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China laboratoire de G eologie Ecole Normale Sup erieure/CNRS UMR8538PSL Research UniversityParis75005France Research Institute of Exploration and development Xinjiang Oilfield CompanyKaramay834000XinjiangChina

Research on reservoir rock stress sensitivity has traditionally focused on unary granular structures,neglecting the binary nature of real reservoirs,especially tight *** the stresssensitive behavior and mathematical characterization of binary granular media remains a challenging *** this study,we conducted online-NMR experiments to investigate the permeability and porosity evolution as well as stress-sensitive control mechanisms in tight sandy conglomerate *** results revealed stress sensitivity coefficients between 0.042 and 0.098 and permeability damage rates ranging from 65.6%to 90.9%,with an average pore compression coefficient of 0.0168—0.0208 MPa ***-scale compression occurred in three stages:filling,compression,and compaction,with matrix pores playing a dominant role in pore *** stress sensitivity of binary granular media was found to be influenced by the support structure and particle *** stress sensitivity was associated with small fine particle size,high fines content,high uniformity coefficient of particle size,high plastic deformation,and low Young's ***-supported samples exhibited a high irreversible permeability damage rate(average=74.2%)and stress sensitivity coefficients(average=0.089),with pore spaces more *** contrast,grain-supported samples showed low stress sensitivity coefficients(average=0.021)at high stress *** on the experiments,we developed a mathematical model for stress sensitivity in binary granular media,considering binary granular properties and nested interactions using Hertz contact deformation and Poiseuille *** describing the change in activity content of fines under stress,we characterized the non-stationary state of compressive deformation in the binary granular structure and classified the reservoir into three *** model was applied for production prediction using actual data from the Mahu reservoir in China,showing that the e

关键词： Stress sensitivity Binary granular medium Tight reservoir Online-NMR Reservoir energy retention rate

Estimation of Daily Global Solar Radiation with Different Sunshine-Based Models for Some Burundian Stations

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Energy and Power Engineering 2024年第1期16卷 1-20页

作者： Mathias Bashahu Gratien Ndacayisaba department of Physics and Technology University of Burundi Bujumbura Burundi department of Physics Ecole Normale Supérieure Bujumbura Burundi

Sunshine duration (S) based empirical equations have been employed in this study to estimate the daily global solar radiation on a horizontal surface (G) for six meteorological stations in Burundi. Those equations include the Ångström-Prescott linear model and four amongst its derivatives, i.e. logarithmic, exponential, power and quadratic functions. Monthly mean values of daily global solar radiation and sunshine duration data for a period of 20 to 23 years, from the Geographical Institute of Burundi (IGEBU), have been used. For any of the six stations, ten single or double linear regressions have been developed from the above-said five functions, to relate in terms of monthly mean values, the daily clearness index () to each of the next two kinds of relative sunshine duration (RSD): and . In those ratios, G0, S0 and stand for the extraterrestrial daily solar radiation on a horizontal surface, the day length and the modified day length taking into account the natural site’s horizon, respectively. According to the calculated mean values of the clearness index and the RSD, each station experiences a high number of fairly clear (or partially cloudy) days. Estimated values of the dependent variable (y) in each developed linear regression, have been compared to measured values in terms of the coefficients of correlation (R) and of determination (R2), the mean bias error (MBE), the root mean square error (RMSE) and the t-statistics. Mean values of these statistical indicators have been used to rank, according to decreasing performance level, firstly the ten developed equations per station on account of the overall six stations, secondly the six stations on account of the overall ten equations. Nevertheless, the obtained values of those indicators lay in the next ranges for all the developed sixty equations:;;;, with . These results lead to assert that any of the sixty developed linear regressions (and thus equations in terms of and ), fit

关键词： Clearness Index Two Kinds of Relative Sunshine Duration Ångström-Prescott linear Model and Four derivatives Statistical Tests Six Burundian Stations

Experimental Study of the Influence of Intrinsic Parameters on the Thermal Reactivity of Sawdust, Polyethylene Terephthalate and Composite

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Journal of Materials Science and Chemical Engineering 2024年第3期12卷 9-20页

作者： Ange Brel Boukongou Timoléon Andzi Barhé Applied Chemistry Research laboratory (lARCA) Ecole Normale Supérieure (ENS) Marien NGOUABI University (UMNG) Brazzaville Congo

Several works have been based on the study of thermal variations in biomass to derive more valuable products such as fuels capable of replacing oil in the event of a crisis or activated carbon used as an adsorbent material, widely used in industry for the elimination of unwanted materials, both in liquid and gaseous environments. A study of thermal parameters such as: heating speed, retention time, drying temperature, carbonization temperature, particle size, was carried out with the aim of determining the characteristic factors of the carbonization of Polyethylene terephthalate (PET), sawdust (SC) and sawdust/polyethylene terephthalate (CPS) mixture. The results of the immediate analysis revealed a very low level of ash in PET (0.013%) compared to the level of ash in sawdust (2.9%), as well as a high level of fixed carbon (82.960%), which suggests the presence of mineral oxides and a significant carbon matrix unlike PET, which indicates a very significant organic matrix (essentially made up of organic matter) with the absence of mineral oxides. The study of thermal parameters showed the water loss from Sawdust (SC) and the Sawdust/Polyethylene terephthalate (CPS) mixture, an increase with temperature, unlike that of PET whose variation is essentially zero. Without heat treatment, sawdust alone contains approximately 7% water. The optimal drying temperature for this study is 110˚C for a stay of 24 hours. It appears that the largest mass losses for the PET samples are between 87.19% and 96.05%, followed by that of the mixture, between 47.33% and 64.37%. And the lowest are observed, those of sawdust (from 24.02% to 62.6%). However, here we can say that the influence of the mass is not great, given the slight difference between the losses by temperature. The results of the study of the influence of grain size showed that the differences are insignificant, even if we vary the diameter of the grains from simple to triple. To better minimize physical constraints such as t

关键词： Intrinsic Parameters Thermal Reactivity Sawdust Polyethylene Terephthalate Composite

2023: Weather and Climate Extremes Hitting the Globe with Emerging Features

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Advances in Atmospheric Sciences 2024年第6期41卷 1001-1016页

作者： Wenxia ZHANG Robin ClARK Tianjun ZHOU laurent lI Chao lI Juan RIVERA lixia ZHANG Kexin GUI Tingyu ZHANG lan lI Rongyun PAN Yongjun CHEN Shijie TANG Xin HUANG Shuai HU State Key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Met Office Hadley Centre Exeter EX13PBUK university of Chinese Academy of Sciences Beijing 100049China laboratoire de Météorologie Dynamique CNRSSorbonne UniversitéEcole Normale SupérieureEcole PolytechniqueParis 75230France Max Planck Institute for Meteorology Hamburg 20146Germany Instituto Argentino de Nivología Glaciología Y Ciencias Ambientales(IANIGLA)CCT CONICETMendoza CP 5500Argentina Shanghai Typhoon Institute China Meteorological AdministrationShanghai 200030China Asia-Pacific Typhoon Collaborative Research Center Shanghai 201306China

Globally,2023 was the warmest observed year on record since at least 1850 and,according to proxy evidence,possibly of the past 100000 *** in recent years,the record warmth has again been accompanied with yet more extreme weather and climate events throughout the ***,we provide an overview of those of 2023,with details and key background causes to help build upon our understanding of the roles of internal climate variability and anthropogenic climate *** also highlight emerging features associated with some of these extreme *** extremes are occurring earlier in the year,and increasingly simultaneously in differing parts of the world(e.g.,the concurrent hot extremes in the Northern Hemisphere in July 2023).Intense cyclones are exacerbating precipitation extremes(e.g.,the North China flooding in July and the libya flooding in September).Droughts in some regions(e.g.,California and the Horn of Africa)have transitioned into flood *** extremes also show increasing interactions with ecosystems via wildfires(e.g.,those in Hawaii in August and in Canada from spring to autumn 2023)and sandstorms(e.g.,those in Mongolia in April 2023).Finally,we also consider the challenges to research that these emerging characteristics present for the strategy and practice of adaptation.

关键词： weather and climate extremes temperature extremes extreme precipitation drought wildfires