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Modelling the viscoplastic behaviour of Callovo-Oxfordian claystone with consideration of damage effect

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 303-316页

作者： Hao Wang Yu-Jun Cui Minh Ngoc Vu Jean Talandier Ecole des Ponts ParisTech Laboratoire Navier/CERMES6 et 8 avenue Blaise PascalMarne La Vallée cedex 277455France Andra R&D DepartmentChâtenay-Malabry92290France

In order to evaluate the performance of deep geological disposal of radioactive waste,an underground research laboratory(URL)was constructed by Andra in the Callovo-Oxfordian(COx)claystone formation at the Meuse/Haute-Marne(MHM).The construction of URL induced the excavation damage of host formations,and the ventilation in the galleries desaturated the host formation close to the gallery ***,it is expected that the mechanical behaviour of COx claystone is *** study presents a constitutive model developed to describe the viscoplastic behaviour of unsaturated and damaged COx *** this model,the unsaturation effect is considered by adopting the Bishop effective stress and the van Genuchten(VG)water retention *** terms of the viscoplastic behaviour,the nonstationary flow surface(NSFS)theory for unsaturated soils is used with consideration of the coupled effects of strain rate and suction on the yield stress.A progressive hardening law is ***,a non-associated flow rule is used,which is similar to that in Barcelona basic model(BBM).In addition,to describe the damage effect induced by suction change and viscoplastic loading,a damage function is defined based on the crack volume *** damage function contains two variables:unsaturated effective stress and viscoplastic volumetric strain,with the related parameters determined based on the mercury intrusion porosimetry(MIP)*** the model validation,different tests on COx claystone under different loading paths are *** between experimental and simulated results indicated that the present model is able to well describe the viscoplastic behaviour of damaged COx claystone,including swelling/shrinkage,triaxial extension and compression,and triaxial creep.

关键词： Callovo-Oxfordian(COx)claystone Excavation damage Time-dependent behaviour Suction Viscoplastic model

Lateral ring compression test applied to a small caliber steel jacket:Identification of a constitutive model

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defence Technology（防务技术） 2024年第6期36卷 133-148页

作者： Yann Coget Yael demarty Christophe Czarnota Anthony Bracq Jean-Sebastien Brest Alexis Rusinek French-German Research Institute of Saint-Louis 5 Rue Du General Cassagnou68300 Saint-LouisFrance laboratoire d'etude des Microstructures et de Mecanique des Materiaux(LEM3) CNRSUniversite de LorraineArts&Metiers ParisTechF-57000 MetzFrance

The evolution of threats and scenarios requires continuous performance improvements of ballistic protections for armed *** a modeling point of view,it is necessary to use sufficiently precise material behavior models to accurately describe the phenomena observed during the impact of a projectile on a protective *** this context,the goal of this paper is to characterize the behavior of a small caliber steel jacket by combining experimental and numerical *** experimental method is based on the lateral compression of ring specimens directly machined from the thin and small *** speeds and temperatures are considered in a quasi-static regime in order to reveal the strain rate and temperature dependencies of the tested *** Finite Element Updating Method(FEMU)is *** results are coupled with an inverse optimization method and a finite element numerical model in order to determine the parameters of a constitutive model representative of the jacket *** of the present model are verified against experimental results and a parametric study as well as a discussion on the identified material parameters are *** results indicate that the strain hardening parameter can be neglected and the behavior of the thin steel jacket can be described by a modeling without strain hardening sensitivity.

关键词： Full metal jacket ammunition Lateral ring compression Inverse identification Numerical simulation

Multivariate Approach to Characterizing Soil Quality of Gabonese’s Ferralitic Soils

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Open Journal of Soil Science 2024年第4期14卷 237-268页

作者： Neil-Yohan Musadji Rolf Gaël Mabicka Obame Michel Mbina Mounguengui Jean Aubin Ondo Lydie-Stella Koutika Eric Ravire Claude Geffroy laboratoire de Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement Des Sciences Fondamentales De L&#8217Ing&#233nieur Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Institut de Chimie des Milieux et Maté riaux De Poitiers (IC2MP) Universit&#233 De Poitiers Poitiers France laboratoire de Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement De Phytotechnologie Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon dé partement De G&#233ologie Facult&#233 Des Sciences Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon laboratoire Pluridisciplinaire des Sciences Ecole Normale Sup&#233rieure Libreville Gabon Centre de Recherche Sur La Productivité et La Durabilit&#233 Des Plantations Industrielles Pointe Noire Republic of Congo Sucaf Gabon Somdiaa Franceville Gabon

Assessing soil quality is essential for crop management and soil temporal changes. The present study aims to evaluate soil quality in the Ferralitic soils context countrywide. This assessment was done using multivariate soil quality indice (SQI) models, such as additive quality index (AQI), weighted quality indexes (WQIadd and WQIcom) and Nemoro quality index (NQI), applied to two approaches of indicator selection: total data set (TdS) and minimum data set (MdS). Physical and chemical soil indicators were extracted from the ORSTOM’s reports resulting from a sampling campaign in different provinces of Gabon. The TdS approach shows soil quality status according to eleven soil indicators extracted from the analysis of 1,059 samples from arable soil layer (0 - 30 cm depth). The results indicated that 87% of all provinces presented a very low soil quality (Q5) whatever the model. Among soil indicators, exchangeable K+ and Mg2+, bulk density and C/N ratio were retained in MdS, using principal component analysis (PCA). In the MdS approach, 50 to 63% of provinces had low soil quality grades with AQI, WQIadd and NQI, whereas the total was observed with WQIcom. Only 25% of provinces had medium soil quality grades with AQI and NQI models, while 12.5% (NQI) and 25% (AQI) presented high quality grades. Robust statistical analyses confirmed the accuracy and validation (0.80 r P ≤ 0.016) of AQI, WQIadd and NQI into the TdS and MdS approaches. The same sensitivity index value (1.53) was obtained with AQI and WQIadd. However, WQIadd was chosen as the best SQI model, according to its high linear regression value (R2 = 0.82) between TdS and MdS. This study has important implications in decision-making on monitoring, evaluation and sustainable management of Gabonese soils in a pedoclimatic context unfavorable to plant growth.

关键词： Gabon Ferralitic Soil Soil Indicators Standard Score Function Soil Quality Indices Sustainable Soil Soil Management

Microbiological Quality of Cyperus esculentus L. Products Sold in Ouagadougou and Bobo dioulasso (Burkina Faso)

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Open Journal of Applied Sciences 2024年第3期14卷 635-642页

作者： Zénabou Semdé Passinguemsin Alice Sonia Tiendrebeogo Bahanla Edwige Oboulbiga Charles Parkouda Hagrétou Sawadogo Lingani laboratoire des Sciences et Technologies des Aliments et Nutrition Département technologie alimentaire IRSAT CNRST Ouagadougou Burkina Faso

This study aimed to assess the microbiological quality of tiger nut (Cyperus esculentus L.) products sold in Ouagadougou and Bobo dioulasso. The microbial load of tubers and tiger nut milk was determined using ISO 4833-1 (2003) standard (total mesophilic aerobic flora), NF ISO 7954 (1998) standard (yeasts and molds), and ISO 4832 (2006) standard (total coliforms, thermotolerant coliforms). The results showed that tiger nut tubers had an average microbial load between 4.86 ± 7.03 × 106 UFC/g and 1.82 ± 2.30 × 107 UFC/g for total mesophilic aerobic flora, from 4.34 ± 10.6 × 105 UFC/g to 3.52 ± 4.54 × 106 UFC/g for yeasts and molds, from 2.23 ± 2.25 × 105 UFC/g to 1.41 ± 2.16 × 105 UFC/g for total coliforms and from 1.83 ± 2.03 × 105 UFC/g to 7.0 ± 10.8 × 104 CFU/g for thermotolerant coliforms. For tiger nut milk samples, the average microbial load varied from 3.48 ± 2.98 × 106 CFU/g to 2.80 ± 5.69 × 107 CFU/g for total mesophilic aerobic flora, from 5.00 ± 7.21 × 104 CFU/g to 1.88 ± 3.31 × 105 CFU/g for yeasts and molds, from 4.58 ± 10.4 × 104 CFU/g to 6.31 ± 9.17 × 105 CFU/g for total coliforms and 7.00 ± 7.00 × 103 CFU/g to 2.87 ± 5.86 × 105 CFU/g for thermotolerant coliforms. This study revealed that the tubers and tiger nut milk sold in Ouagadougou and Bobo dioulasso had a high microbial load which could lead to the degradation of these products and food poisoning for consumers.

关键词： Cyperus esculentus L. Tiger Nut Tubers Tiger Nut Milk Microbiological Quality

Purity-dependent Lorenz number,electron hydrodynamics and electron-phonon coupling in WTe_(2)

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 153-158页

作者： Wei Xie Feng Yang Liangcai Xu Xiaokang Li Zengwei Zhu Kamran Behnia Wuhan National High Magnetic Field Center and School of Physics Huazhong University of Science and TechnologyWuhan 430074China laboratoire de Physique et d’etude des Matériaux(ESPCI-CNRS-Sorbonne Université)PSL University Paris 75005France

We present a study of electrical and thermal transport in Weyl semimetal WTe_(2)down to 0.3 *** Wiedemann-Franz law holds below 2 K and a downward deviation starts *** deviation is more pronounced in cleaner samples,as expected in the hydrodynamic picture of electronic transport,where a fraction of electron-electron collisions conserve *** are the dominant heat carriers and their mean-free-path does not display a Knudsen *** is presumably a consequence of weak anharmonicity,as indicated by the temperature dependence of the specific *** momentum exchange between phonons and electrons leads to quantum oscillations of the phononic thermal ***-Grüneisen picture of electron-phonon scattering breaks down at low temperature when Umklapp ph-ph collisions cease to be a sink for electronic flow of *** with semi-metallic Sb shows that normal ph-ph collisions are amplified by *** both semimetals,at cryogenic temperature,e-ph collisions degrade the phononic flow of energy but not the electronic flow of momentum.

关键词： thermal conductivity Wiedemann-Franz law electron hydrodynamics electron-phonon coupling

Finite-temperature ductility-brittleness and electronic structures of Al_(n)Sc(n=1,2 and 3)

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Rare Metals 2024年第8期43卷 3974-3989页

作者： Xue-Qian Wang Ying Zhao Hao-Xuan Liu Shu-Chen Sun Hong-Bo Yang Jia-Min Zhong Gan-Feng Tu Song Li Yu-dong Zhang Claude Esling Hai-Le Yan Liang Zuo Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China Rare Earth Functional Materials(Xiong'an)Innovation Center Co. Ltd.Xiong'an 071700China laboratoire d'étude des Microstructures et de Mécanique des Matériaux(LEM3) Unikersitéde Lorraine57045MetzFrance

Finite-temperature ductility-brittleness and electronic structures of Al_(3)Sc,Al_(2)Sc and AlSc are studied comparatively by first-principles calculations and ab initio molecular *** show that Al_(3)Sc and Al_(2)Sc are brittle at both ground state and finite temperatures,while AlSc possesses a significantly superior *** ground state,AlSc is ductile from Pugh's and Poisson's criteria,while it is brittle in Pettifor's *** ductility of all Al_(3)Sc,Al_(2)Sc and AISc improves greatly with the elevated ***,the Cauchy pressure of AlSc undergoes a transition from negative to *** T>600 K,AlSc is unequivocally classified as ductile from all criteria *** all compounds,the Al-Al bond originated from s-p and p-p orbital hybridizations,and the Al-Sc bond dominated by p-d covalent hybridization,are the first and second strongest chemical bonds,*** explain the difference in mechanical properties,the mean bond strength(MBS)is introduced in this *** weaker Al-Al bond in AlSc,leading to a smaller MBS,could be the origin of the softer elastic stiffness and superior intrinsic *** longer length of the Al-Al bond in AlSc is responsible for its weaker bond ***,the enhanced metallicity of the Al-Al bond in AlSc would also contribute to its exceptional *** longer length of the Al-Al bond in AISc is responsible for its weaker bond ***,the enhanced metallicity of the Al-Al bond in AlSc would also contribute to its exceptional ductility.

关键词： Al-Sc Target materials Intrinsic ductility Finite-temperature elastic constant First-principles calculation

Technical-Economic Performance, Carcass and Meat Quality of COBB500 Broilers Fed Rations Incorporating Mango By-Product Feeds in Ivory Coast (West Africa)

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Open Journal of Animal Sciences 2024年第1期14卷 1-13页

作者： Timbilfou Kiendrébéogo Alidjata Traoré etienne Sodre drissa Barry Isidor Ouedraogo Marcelle Grace Koidja Vianney Tarpaga Centre National de la Recherche Scientifique et Technologique Institut de l’Environnement et de Recherches Agricoles Laboratoire de Recherches en Production et Santé Animales (LAREPSA) Bobo-Dioulasso Burkina Faso Centre National de la Recherche Scientifique et Technologique Institut de l’Environnement et de Recherches Agricoles Laboratoire Central d’Horticulture (LCH) Bobo-Dioulasso Burkina Faso laboratoire d’etude des Ressources Naturelles et des Sciences de l’environnement (LERNSE) Ecole Doctorale Sciences Naturelles et Agronomie (ED-SNA) Université Nazi BONI Bobo-Dioulasso Burkina Faso Université Catholique de l’Afrique de l’Ouest (UCAO) Section du Burkina Faso Bobo-Dioulasso Burkina Faso direction Régionale de l’Agriculture des Ressources Animales et Halieutiques de l’Est Fada Burkina Faso

The study evaluated the growth performance and carcass quality of COBB500 broilers fed two experimental rations incorporating feed and mango fine Ed10 for a batch of 83 birds, Ed20 (batch of 83 birds) in comparison with a commercial control ration CCd (84 birds). For this purpose, 250 day-old chicks of this breed were purchased in Korhogo and transported to Tengréla in Ivory Coast for rearing. The results show that substituting mango provender ans and mango seed flour for maize resulted in rations with costs per kgMS of 215.35FCFA, 2016.93FCFA and 320FCFA for the Ed10, Ed20 and CCd rations respectively. The production costs per kg of chicken (FCPkgLW) of the CCd ration were significantly higher than those of the Ed10 and Ed20 (p 0.05). AdGs were significantly different and decreasing from CCd, Ed20 to Ed10 (p 0.05). Average weights at 42nd day for Ed20 and CCd were homogeneous (p > 0.05) and significantly higher than for Ed10 (p 0.05). By day 49th the average weight of Ed20 had reached and exceeded that of CCd by day 42nd. PSLW, HCW and CCW were significantly different and decreasing from CCW, Ed20 to Ed10 (p 0.05). Average hot (HCY) and cooled (CCY) carcass yields of Ed20 and CCd rations were comparable (p > 0.05) and significantly higher than those of Ed10 ration (p = 0.009) and 0.003). Average drumstick and neck weights were significantly higher and lower for CCd, Ed20 and Ed10 (p 0.05). For all other parts of the cut, the average weights of the CCd ration were significantly higher (p 0.05) than those of the Ed20 and Ed10 rations, which were homogeneous (p 0.05). The incorporation of mango provender and mango seed flour in broiler rations offers the prospect of reduced production costs, less competition between man and animals over cereals, and lean meat production tha

关键词： Broiler COOB 500 Chickens Mango Feed Carcass Characteristics Tengrela Ivory Coast

Experimental Investigation of the Stability of the Performance Characteristics of a Photovoltaic Module in the Face of Environmental and Meteorological Factors

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Open Journal of Applied Sciences 2024年第2期14卷 589-608页

作者： Adingra Paul Arsène Kouassi Siaka Touré diakaridja Traoré laboratoire des Sciences de la Matière de l’Environnement et de l’Energie Solaire (LASMES) Unité de Formation et de Recherche des Sciences des Structures de la Matière et Technologie (UFR-SSMT) Université Félix Houphou&#235t Boigny Abidjan C&#244te d’Ivoire

The explosive technological improvement of photovoltaic systems as well as the necessity of populations to come to less expensive energy sources, that have led to an implosion at the level of solar panel manufacturers. This causes a large flow of these equipments to developing countries where the need is high, without any quality control. That conducted an experimental investigation on the performance characteristics of a 250 wp monocrystalline silicon photovoltaic module in other to check the verification and quality control. Most of these PV panels which often have missing informations are manufactured and tested in places that are inadequate for our environmental and meteorological conditions. Also, their influences on the stability of internal parameters were evaluated in order to optimize their performance. The results obtained at maximum illumination (1000 w/m2) confirmed those produced by the manufacturer. The analysis of these characteristics showed that the illumination and the temperature (meteorological factors) influenced at most the stability of the internal characteristics of the module in the sense that the maximum power increased very rapidly beyond 750 w/m2 but a degradation of performance was accentuated for a temperature of the solar cells exceeding 50°C. The degradation coefficients were evaluated at -0.0864 V/°C for the voltage and at -1.6248 w/°C for the power. The 10° inclination angle of the solar panel proved to be ideal for optimizing overall efficiency in practical situations.

关键词： Renewables Energies Instruments Internal Parameters of Photovoltaic Panel Monocrystalline Photovoltaic Panel Solar Energy Production Energy Intermittence

A New Multiobjective Particle Swarm Optimization Using Local displacement and Local Guides

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Open Journal of Optimization 2024年第2期13卷 31-49页

作者： Saïd Charriffaini Rawhoudine Abdoulhafar Halassi Bacar laboratoire des Mathmatiques Statistiques Informatique et Applications (LMSIA) Dpartement des Mathmatiques Physique-Chimie et Informatique Facult des Sciences et Techniques Universit des Comores Moroni Comoros

This paper introduces a novel variant of particle swarm optimization that leverages local displacements through attractors for addressing multiobjective optimization problems. The method incorporates a square root distance mechanism into the external archives to enhance the diversity. We evaluate the performance of the proposed approach on a set of constrained and unconstrained multiobjective test functions, establishing a benchmark for comparison. In order to gauge its effectiveness relative to established techniques, we conduct a comprehensive comparison with well-known approaches such as SMPSO, NSGA2 and SPEA2. The numerical results demonstrate that our method not only achieves efficiency but also exhibits competitiveness when compared to evolutionary algorithms. Particularly noteworthy is its superior performance in terms of convergence and diversification, surpassing the capabilities of its predecessors.

关键词： Particle Swarm Optimization Multiobjective Optimization Attractor-Based displacement Square Root distance Crowding distance