检索结果-南通市图书馆

International Journal of Geosciences 2025年第1期16卷 20-30页

作者： Idrissa Sourabié Abidina Diabaté Emmanuel Wambi Sawadogo Bruno Korgo Christian Zoundi Allain Doua Gnabahou denis Ouédraogo Frédéric Ouattara laboratoire de Chimie Analytique de Physique Spatiale et nergtique (L@CAPSE) Dpartement de Physique Universit Norbert ZONGO Koudougou Burkina Faso laboratoire denergies thermiques REnouvelables (L.E.T.RE) Dpartement de Physique Universit Joseph KI-ZERBO Ouagadougou Burkina Faso

this article is part of the ongoing study of the moderate geomagnetic activity of corotation. the aim here is to examine ionospheric anomalies through variations in Total Electronic Content (TEC) recorded at the Koudougou GPS station over solar cycle 24 during periods of corotation activity. through the diurnal variations by solar phase, we observed a TEC peak at 14:00 TL. the TEC data analysed revealed winter, annual and semi-annual anomalies. However, the equinoctial anomaly was insignificant during corotation activity at the Koudougou station during solar cycle 24.

关键词： Geomagnetic Activity Total Electronic Content Ionospheric Anomalies Equinoctial Corotation Activity

Schwarzschild black hole surrounded by a cloud of strings in the background of perfect fluid dark matter

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2025年第02期 224-240页

作者： B.Hamil B.C.Lütfüo?lu laboratoire de physique Mathématique et Subatomique Faculté des Sciences ExactesUniversité Constantine 1 department of Physics Faculty of ScienceUniversity of Hradec Kralove

this manuscript investigates a Schwarzschild black hole surrounded by perfect fluid dark matter embedded in a cloud of strings. the effects of its surroundings on thermodynamics, timelike and null geodesics, shadows,and quasinormal modes are analyzed. It is demonstrated that changes in spacetime, induced by the surrounding environment, significantly influence the stability, thermal phases, energy dynamics, particle trajectories, and observable features of the black hole's shadow, as well as its oscillation frequency and decay rate.

关键词：

Influence of Magnetic Field and Temperature on the Transient density and Voltage in a Radial Junction Solar Cell in Dynamic Regime under Pulsed Multispectral Illumination

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Applied Sciences 2025年第1期15卷 42-52页

作者： Moussa Ouedraogo Nazé Yacouba Traore Alain Diasso Raguilignaba Sam François Zougmore laboratoire de Matriaux dHliophysique et Environnement (LaMHE) Dpartement de Physique UFR/ST Universit Nazi Boni Bobo Dioulasso Burkina Faso laboratoire de Matriaux et Environnement Dpartement de Physique UFR/SEA Universit Joseph Ki-Zerbo Ouagadougou Burkina Faso

this study examines the influence of magnetic field and temperature on the transient voltage of a polycrystalline silicon radial junction solar cell in a dynamic regime under multispectral illumination. Radial junction solar cells represent a major advancement in photovoltaic technologies, as they optimize light absorption and charge collection efficiency. the focus is on the impact of the magnetic field and temperature on the decay of transient voltage, which provides crucial information on recombination processes and the lifetime of minority carriers. the results reveal that the magnetic field tends to increase the transient voltage by directly affecting the transient electron density. Indeed, for B > 7 × 10−5 T, the magnetic field prolongs the relaxation time by increasing the transient voltage amplitude. Additionally, rising temperatures accelerate (ranging from 290 K to 450 K) recombination processes, thereby reducing the transient voltage, although this effect is moderated by the presence of a magnetic field. the study highlights the complex interaction between magnetic field and temperature, with significant impacts on the transient behaviour.

关键词： Electrons Radial Junction Transient Voltage Magnetic Field Operating Temperature

design and Optimization of Terracotta Tube-Based Direct Evaporative Cooling Exchanger: An Analytical Approach to Heat and Mass Transfer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Applied Sciences 2025年第1期15卷 352-373页

作者： Windnigda Zoungrana Makinta Boukar Ousmane Coulibaly Guy Christian Tubreoumya Antoine Bere laboratoire denergtique dElectronique dElectrotechnique dAutomatique et dinformatique Industrielle Universit Abdou Moumouni Niamey Niger laboratoire de physique et de Chimie de lEnvironnement Universit Joseph Ki Zerbo Ouagadougou Burkina Faso

this study develops an analytical model to evaluate the cooling performance of a porous terracotta tubular direct evaporative heat and mass exchanger. By combining energy and mass balance equations with heat and mass transfer coefficients and air psychrometric correlations, the model provides insights into the impact of design and operational parameters on the exchanger cooling performance. Validated against an established numerical model, it accurately simulates cooling behavior with a Root Mean Square deviation of 0.43 - 1.18˚C under varying inlet air conditions. the results show that tube geometry, including equivalent diameter, flatness ratio, and length significantly influences cooling outcomes. Smaller diameters enhance wet-bulb effectiveness but reduce cooling capacity, while increased flatness and length improve both. For example, extending the flatness ratio of a 15 mm diameter, 0.6 m long tube from 1 (circular) to 4 raises the exchange surface area from 0.028 to 0.037 m2, increasing wet-bulb effectiveness from 60% to 71%. Recommended diameters range from 5 mm for tubes under 0.5 m to 1 cm for tubes 0.5 to 1 m in length. Optimal air velocities depend on tube length: 1 m/s for tubes under 0.8 m, 1.5 m/s for lengths of 0.8 to 1.2 m, and up to 2 m/s for longer tubes. this model offers a practical alternative to complex numerical and CFD methods, with potential applications in cooling tower optimization for thermal and nuclear power plants and geothermal heat exchangers.

关键词： Analytical Modeling Porous Terracotta Tube Direct Evaporative Cooling Heat and Mass Exchanger Performance Optimization

Ab initio simulation of the sum-frequency generation response of optically active liquids in the presence of a dc electric field —determination of the absolute molecular configuration

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2014年第10期57卷 1405-1408页

作者： CHAMPAGNE Benot QUINET Olivier laboratoire de Chimie théorique Unité de Chimie Physique Théorique et Structurale Université de Namur

Quantum chemical computations have been performed to evaluate the first and second hyperpolarizability quantities of the interference term, linear in the external static electric field, that appear in the electric field-induced sum-frequency generation signal of chiral liquids. these are performed at the time-dependent Hartree-Fock level on the prototypical 1,1′-bi-2-naphtol chiral species.

关键词： second and third hyperpolarizabilities chirality nonlinear optics time-dependent Hartree-Fock

Capillary effect on the sloshing of a fluid in a rectangular tank submitted to sinusoidal vertical dynamical excitation

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2014年第2期26卷 326-338页

作者： MEZIANI Bachir OURRAD Ouerdia laboratoire de physique théorique Université A. Mira de Bejaia Campus de targua Ouzemour

Surface tension effects on fluid sloshing in a tank subjected to external excitation has been less studied. this work aims at understanding this phenomenon in order to derive practical solutions to problems faced in several engineering. A tank containing a fluid with a free surface is submitted to gravity and capillary forces and subject to external dynamic excitation. Introduction of vertical sinusoidal dynamical excitation leads to a problem of paramtric oscillations governed by the Mathieu equation. Analysis of the Mathieu equation shows the existence of stable and unstable regions in the stability diagram. Some results induced by harmonic excitations on the fluid sloshing are presented. When the external dynamical excitation amplitude ~ is small, periodic solutions appear in stable regions and when e increases, the fluid behavior is not perfectly periodic and the amplitudes are not regular. Nonlinear effects make the behavior of the fluid complicated and render it almost unpredictable. In stable regions, the solution remains bounded at any time. When changing the perturbation parameter 6, the phase difference increases and also with the increase of the surface tension.

关键词： parametric sloshing capillary effects stability

A Review of Research Activities for the Perspective of a Smart Electricity Grid in Burkina Faso

在线全文

学校读者我要写书评

暂无评论

Smart Grid and Renewable Energy 2025年第1期16卷 1-12页

作者： Brice Junior Carmel Wendenda Ilboudo Ollé Michel Kam Raguilignaba Sam laboratoire de Matriaux dHeliophysique et Environnement (LaMHE) Dpartement de Physique Universit Nazi BONI Bobo-Dioulasso Burkina Faso laboratoire de Matriaux et Environnement (LAME) Dpartement de Physique Universit Joseph KI ZERBO Ouagadougou Burkina Faso Science du Numrique Universit Virtuelle du Burkina Faso (UV-BF) Ouagadougou Burkina Faso

this review explores the research activities surrounding the development and integration of smart electricity grids in Burkina Faso, a landlocked and arid territory in West Africa and one of the poorest countries in the world with significant energy challenges. It examines the current state of energy infrastructure in Burkina Faso, focusing on the integration of renewable energy sources, particularly solar photovoltaics. It highlights the role of smart grid technologies in enabling the efficient integration of renewable energy, improving grid stability and facilitating rural electrification. Additionally, the review addresses key challenges such as inadequate infrastructure, regulatory gaps and financial constraints that hinder the deployment of smart grids in the country. By analysing existing research and ongoing projects, this paper provides a comprehensive overview of the opportunities and barriers to implementing a smart electricity grid in Burkina Faso and offers recommendations for future development and policy frameworks.

关键词： Smart Grid Smart Building decentralised Energy Production Photovoltaic Renewable Energy

Comparative Study of Entanglement and Wigner Function for Multi-Qubit GHZ-Squeezed State

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in theoretical Physics 2017年第12期67卷 729-734页

作者： Fatima-Zahra Siyouri laboratoire de physique thèorique Département de Physique Faculté des Sciences Université Mohammed Ⅴ-Agdal

In this paper we address the possibility of using the Wigner function to capture the quantum entanglement present in a multi-qubit system. For that purpose, we calculate both the degree of entanglement and the Wigner function for mixed tripartite squeezed states of Greenberger–Horne–Zeilinger(GHZ) type then we compare their behaviors. We show that the role of Wigner function in detecting and quantifying bipartite quantum correlation [Int. J. Mod. Phys. B30(2016) 1650187] may be generalized to the multipartite case.

关键词： negativity of Wigner function entanglement squeezed states tripartite GHZ non-classicality

thermal pairing treatment within the path integral formalism

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第11期48卷 106-119页

作者： M.Fellah N.H.Allal M.R.Oudih laboratoire de physique théorique-Facultéde physique-USthB BP32 El-Alia16111 Bab-Ezzouar-Alger-Algeria

A method for the treatment of pairing correlations at finite temperature is proposed within the path integral formalism,based on the square root extraction of the pairing term in the Hamiltonian of the *** equations and expressions for the pairing gap parameterΔ,energy E,and heat capacity C are *** formalism is first tested using the Richardson model,which enables comparison with an exact *** results obtained using this formalism are also compared with the finite temperature BCS(FTBCS)*** improvement over the FTBCS model is noted,especially at low ***,the agreement between theΔvalues of this study and the exact values is good at low *** leads to better agreement between the values of E and C of this model and the exact values than with the FTBCS ***,a critical value of temperature ***,realistic cases are considered using single-particle energies of a deformed Woods-Saxon mean-field for the nuclei ^(162)Dy and ^(172)*** the framework of the current approach,pairing effects persist beyond the FTBCS critical ***,at low temperatures,a good agreement between the model and semiexperimental values of the heat capacity is observed,and a clear improvement compared to the FTBCS method is *** is no more the case at higher temperatures.

关键词： nuclear structure pairing temperature

the Fourier space restricted Hartree-Fock method for the electronic structure calculation of linear poly(tetrafluoroethylene)

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2014年第10期57卷 1355-1362页

作者： FRIPIAT Joseph G. HARRIS Frank E. laboratoire de Chimie théorique Unité de chimie physique théorique et structurale University of NamurRue de Bruxelles department of Physics University of Utah Quantum theory Project University of Florida

Building on the pioneering work of Jean-Marie Andre and working in the laboratory he founded, the authors have developed a code called FT-1D to make Hartree-Fock electronic structure computations for stereoregular polymers using Ewald-type con- vergence acceleration methods. that code also takes full advantage of all line-group symmetries to calculate only the minimal set of two-electron integrals and to optimize the computation of the Fock matrix. the present communication reports a bench- mark study of the FT-1D code using polytetrafluoroethylene （PTFE） as a test case. Our results not only confirm the algorith- mic correctness of the code through agreement with other studies where they are applicable, but also show that the use of con- vergence acceleration enables accurate results to be obtained in situations where other widely-used codes （e.g., PLH and Crys- tal） fail. It is also found that full attention to the line-group symmetry of the PTFE polymer leads to an increase of between one and two orders of magnitude in the speed of computation. the new code can therefore be viewed as extending the range of electronic-structure computations for stereoregular polymers beyond the present scope of the successful and valuable code Crystal.

关键词： poly(tetrafluoroethylene) band structure Fourier-space Hartree-Fock lattice sum Ewaid