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Analysis and Predictability of Dry Spell Lengths Observed in Synoptic Stations of Benin Republic (West Africa)

american Journal of Climate Change 2021年第4期10卷 597-618页

作者： médard noukpo Agbazo Joseph adébiyi adéchinan Gabin Koto n'gobi Joseph Bessou international Chair in mathematical Physics and Applications (iCmPA-UnESCO Chair) Université d’Abomey-Calavi Abomey-Calavi Bénin Laboratoire de Physique du Rayonnem.nt (LPR) Université d’Abomey-Calavi Abomey-Calavi Bénin Départem.nt de Physique Faculté des Sciences et Techniques Université Nationale des Sciences Technologies Ingénierie et Mathématiques (UNSTIM) Abomey Bénin Agence nationale de la météorologie du Bénin (mETEO BEnin) Cotonou Bénin

The complex behavior and predictability of the Dry Spell Lengths (DSL) series obtained in Benin synoptic stations, from 1951 to 2010 are analyzed in this paper using a fractal approach. The synoptic stations are located in Cotonou, Bohicon, Save (subequatorial climate), and Parakou, natitingou, Kandi (Sudanian climate). The DSLs are computed by considering four thresholds level, R0 = {1.0, 1.5, 2.0 and 5.0} mm/day. The fractal trace is estimated for dry spell density by the mean of the “Dry Spell Spell” (DSS) n-index. The rescaled range method is used to determine the predictability of DSL. By analyzing the DSS, results show that low DSS n-index values (n-index more favored in the northern part of Benin than in the southern region, whereas, high values of DSS n-index (n-index > 0.4) occur preferentially in the southern part. Therefore, during 1951-2010, the Sudanian region presents frequent wet spells, alternated with short dry spells than in the subequatorial one. However, a high degree of long dry spell persistence, followed by short dry events is observed in the subequatorial region than in the Sudanian one. The longest DSL is observed in the subequatorial region, especially in Cotonou. Except for the Kandi station, the DSLs series obtained at synoptic stations are characterized by persistence. Therefore, autoregressive processes could be applied to the DSL series. Generally, the physical process governing dry spells observed at Save, natitingou, and Bohicon are consistently predictable than the process governing the stations of the Cotonou and Parakou. However, at Kandi station, the DSL process approximates the usual Brownian motion, and it is, therefore, unpredictable or difficult to predict.

关键词： Hurst Exponent n-index DSL Predictability Complex Behavior Benin

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mechanical and Electrical Properties of the Ternary Ag-Sb-Zn System

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Acta metallurgica Sinica(English Letters) 2014年第1期27卷 47-54页

作者： m.Premovi D.mini D.manasijevi Vladan osovi D.Zivkovi i.Dervisevi n.Talijan Faculty of Technical Science University in PristinaKosovska MitrovicaSerbia Technical Faculty University of Belgrade institute of Chemistry Technology and MetallurgyUniversity of Belgrade

This paper presents comparative review of experimental and thermodynamic assessment of ternary Ag-Sb-Zn system. isothermal section of the Ag-Sb-Zn system at 300 ~C has been calculated by CALPHad method using ther- modynamic parameters from literature. microstructural analysis of a number of alloys was carried out by scanning electron microscopy and optical microscopy, whereas chemical composition of observed phases was analyzed using energy- dispersive X-ray spectroscopy. Hardness of selected alloys from four vertical sections was determined using Brinell hardness test and additionally by micro Vickers hardness test. Electrical conductivity of a number of alloys in the ternary Ag-Sb-Zn system was experimentally determined. Good overall agreem.nt between experimental and calculated values was obtained.

关键词： Ag-Sb-Zn system isothermal section microstructure Brinell hardness micro Vickers hardness: Electrical conductivitv

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Junction properties and conduction mechanism of new terbium complexes with triethylene glycol ligand for potential application in organic electronic device

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Journal of Rare Earths 2014年第7期32卷 633-640页

作者： n.K.Za’aba m.A.mohd Sarjidan W.H.Abd.majid Eny Kusrini muhammad i.Saleh Low Dimensional materials Research Centre Physics DepartmentUniversity Malaya Department of Chemical Engineering Faculty of EngineeringUniversitas Indonesia School of Chemical Sciences Universiti Sains Malaysia

Terbium-picrate triethylene glycol（EO3-Tb-Pic） complex was prepared in thin film and single layer device structure of iTO/EO3-Tb-Pic/Al, using spin coating technique. The UV-Vis absorption spectroscopy analysis was performed to evaluate the electronic molecular transition of the complex. The optical band gap, Eg estimated from the Tauc model revealed that EO3-Tb-Pic thin film exhibited a direct transition with Eg of 2.70 eV. The electronic parameters of the iTO/EO3-Tb-Pic/Al device such as the ideality factor n, barrier height Φb, saturation current io, and series resistance Rs, were extracted from the conventional lni-V, Cheung＇s functions and norde＇s method. it was found that the evaluated parameters calculated from norde＇s and Cheung＇s methods were consistent with those calculated from the conventional i-V method. in the double logarithmic i-V plot, three distinct regions based on the slope were identified, and the conduction mechanisms were discussed and explained. The mobility, μ value was estimated from SCLC region as 2.58×10^–7 cm2/（V·s）. This newly obtained lanthanide complex may be potentially utilized in electronic devices.

关键词： terbium-picrate complex triethylene glycol Tauc model optical band gap current-voltage rare earths

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increased serum nitric oxide and malondialdehyde levels in patients with acute intestinal amebiasis

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Asian Pacific Journal of Tropical Biomedicine 2011年第6期1卷 478-481页

作者： namiduru ES Tarakcloglu m namiduru m Kocabas R Erbagcl B meram i Karaoglan i Yilmaz n Cekmen m University of Gaziantep Faculty of MedicineDepartment of Biochemistry University of Gaziantep Faculty of MedicineDepartment of Infectious Disease

Objective:To determine the level of oxygen-nitrogen stress parameters in the pathogenesis of ***:Twenty-four acute intestinal amebiasis patients and 20 healthy controls were enrolled in the present *** malondialdehyde and nitric oxide levels were determined ***:Serum raalondialdehyde and nitric oxide levels were significantly higher in acute intestinal amebiasis patients than healthy controls(Pnclusions:These results suggest that oxidative and nitrosative stress may play a major role in tissue damage in acute intestinal amebiasis *** these parameters can be used to supplem.nt the conventional microscopic method for reliable diagnosis of intestinal amebiasis.

关键词： amebiasis malondialdehyde nitric oxide

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Analytical Determination of Collisionless Sheath Properties for Triple Frequency Capacitively Coupled Plasma

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Plasma Science and Technology 2015年第2期17卷 141-146页

作者： m.T.RAHmAn m.n.A.DEWAn Department of Electrical and Electronic Engineering Bangladesh University of Engineering and Technology

A triple frequency capacitively coupled plasma （TF-CCP） has been considered to investigate the behavior of the sheath parameters. A self-consistent time-independent collisionless model has been developed. The sheath width and potential are calculated using the present model and compared with those calculated using a single-frequency （SF）, a dual-frequency （DF） and a triple-frequency （TF） model for time independent collisionless cases. The sheath motion and sheath potential are found to be larger compared with those of SF and DF CCPs for an inhomogeneous sheath, and that of TF CCP for a homogeneous sheath. The effects of the source parameters, i.e., current magnitudes, frequencies and phase difference, on the sheath parameters are investigated. The sheath parameters show higher values at higher source currents whereas they decrease with the increase of excitation frequencies. it has also been found that, by the proper choice of source frequencies and phase differences, it is possible to adjust the energy of ions when they hit the electrode.

关键词： capacitively coupled plasma collisionless sheath triple frequency sheath parameters

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Comprehensive investigation of stress intensity factors in rotating disks containing three-dimensional semi-elliptical cracks

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Applied mathematics and mechanics(English Edition) 2017年第11期38卷 1565-1578页

作者： m.FAKOOR S.m.n.GHOREiSHi Faculty of new Sciences and Technologies University of Tehran Tehran 14395-1561 Iran

initiation and propagation of cracks in rotating disks may cause catastrophic failures. Therefore, determination of fracture parameters under different working con- ditions is an essential issue. in this paper, a comprehensive study of stress intensity factors （SiFs） in rotating disks containing three-dimensional （3D） semi-elliptical cracks subjected to different working conditions is carried out. The effects of mechanical prop- erties, rotational velocity, and orientation of cracks on SiFs in rotating disks under cen- trifugal loading are investigated. Also, the effects of using composite patches to reduce SiFs in rotating disks are studied. The effects of patching design variables such as mechanical properties, thickness, and ply angle are investigated separately. The modeling and analytical procedure are verified in comparison with previously reported results in the literature.

关键词： stress intensity factor (SiF) semi-elliptical crack rotating disk finite ele-ment analysis (FEA)

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mixing features in an electromagnetic rectangular micromixer for electrolyte solutions

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Journal of Hydrodynamics 2017年第4期29卷 668-678页

作者： m.m.Wen C.n.Kim Department of mechanical Engineering Graduate School Kyung Hee University Department of mechanical Engineering College of Engineering Kyung Hee University

in this study, a new magnetohydrodynamic（mHD） mixer for electrolyte solutions with pumping function is reported, and the mixing performance of the device for two different electrolyte solutions is numerically examined in a uniform magnetic field. Application of different potentials to different electrodes allows the current to be induced. The combination of the induced current and magnetic field yields Lorentz force, resulting in the fluid motion. The numerical simulation for the flows in the device is carried out with commercial software CFX. The validity of CFX code for the present numerical model is presented. The mixing performance of the fluids is investigated in many different cases with different combinations of input voltage of the electrode. This study shows that the mixing performance can be enhanced by applying spatially alternating positive and negative voltages to the electrodes. The present simulation results show that with a magnetic field intensity lower than 0.5 T, a voltage difference smaller than 2.0 V, and an electric conductivity of electrolyte solution of 1.5 S/m the pumping capabilities ranging 1.6×10^（-7）-3.6×10^（-6） kg/s and the mixing indexes higher than 0.90 can be obtained with sophisticated designs of the micromixer.

关键词： mixer electrolyte solution Lorentz force CFX

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Thermomagnetic viscoelastic responses in a functionally graded hollow structure

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Acta mechanica Sinica 2011年第4期27卷 567-577页

作者： m.n.m.Allam R.Tantawy mathematics Department Faculty of ScienceMansoura University

This paper presents an analytical solution for the interaction of electric potentials, electric displacem.nts, elastic deformations, and thermoelasticity, and describes electromagnetoelastic responses and perturbation of the magnetic field vector in hollow structures （cylinder or sphere）, subjected to mechanical load and electric potential. The material properties, thermal expansion coefficient and magnetic permeability of the structure are assumed to be graded in the radial direction by a power law distribution. in the present model we consider the solution for the case of a hollow structure made of viscoelastic isotropic material, reinforced by elastic isotropic fibers, this material is considered as structurally anisotropic material. The exact solutions for stresses and perturbations of the magnetic field vector in FGm hollow structures are determined using the infinitesimal theory of magnetothermoelasticity, and then the hollow structure model with viscoelastic material is solved using the correspondence principle and illyushin＇s approximation method. Finally, numerical results are carried out and discussed.

关键词： Functionally graded material Viscoelasticity Perturbation of magnetic field vector magnetoelasticity

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Traces of Defects in the Electronic Structure of Porous ni—Ti Alloys

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Journal of materials Science & Technology 2013年第4期29卷 344-348页

作者： O.m.Ozkendir E.Cengiz E.Tirasoglu mehmet Kaya i.H.Karahan n.Orhan Tarsus Technical Faculty of Education Mersin UniversityTarsusTurkey institute for molecular Science UVSOR FacilityOkazaki 444-8585Japan Science Faculty Department of PhysicsKaradeniz Technical UniversityTrabzonTurkey Vocational School Adiyaman University.Adiyaman 02040Turkey Department of mechanical Engineering Texas A&M UniversityCollege StationTX 77843USA Faculty of Arts and Sciences Department of PhysicsMustafa Kemal UniversityHatayTurkey Faculty of Technology Department of Metallurgy and Material EngineeringFirat UniversityElazigTurkey

The electronic structures of ni-Ti shape-memory alloy samples were investigated by X-ray absorption fine structure （XAFS） spectroscopy both experimentally and theoretically. in the experimental section, the samples were measured at low temperature to determine the persistent traces of both preheating process and atomic concentration effects on the crystal and electronic structure by X-ray absorption near-edge structure （XAnES） spectroscopy. As a second step, the extended-X-ray absorption fine structure （EXAFS） calculations, which are based on different choices of one electron potentials according to Ti coordinations by using the real space multiple scattering method FEFF 8.2 code, were performed. The crystallographic and electronic structures of the porous ni-Ti alloys were tested at various temperatures ranging from 5 to 1323 K.

关键词： Electronic structure Porous ni-Ti alloys Shape memory effect Transition metals

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advancing healthcare through laboratory on a chip technology:Transforming microorganism identification and diagnostics

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World Journal of Clinical Cases 2025年第3期13卷 9-19页

作者： Carlos m Ardila Department of Basic Sciences Biomedical Stomatology Research GroupUniversidad de Antioquia U de AMedellín 0057Colombia

in a recent case report in the World Journal of Clinical Cases,emphasized the crucial role of rapidly and accurately identifying pathogens to optimize patient treatment ***-on-a-chip(LOC)technology has emerged as a transformative tool in health care,offering rapid,sensitive,and specific identification of *** editorial provides a comprehensive overview of LOC technology,highlighting its principles,advantages,applications,challenges,and future *** studies from the field have dem.nstrated the practical benefits of LOC devices in clinical diagnostics,epidemiology,and food *** studies have underscored the superiority of LOC technology over traditional methods,showcasing improvem.nts in speed,accuracy,and *** future integration of LOC with biosensors,artificial intelligence,and data analytics promises further innovation and *** call to action emphasizes the importance of continued research,investment,and adoption to realize the full potential of LOC technology in improving healthcare outcomes worldwide.

关键词： Laboratory-on-a-chip microorganism identification Diagnostics Point-ofcare testing Biosensors

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