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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

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

Decomposition mechanisms of nuclear-grade cationic exchange resin by advanced oxidation processes:Statistical molecular fragmentation model and DFT calculations

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Journal of Environmental Sciences 2024年第1期135卷 433-448页

作者： Xiang Meng Pierre Désesquelles Lejin Xu Department of Nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science&TechnologyWuhan 430074China CNRS Laboratoire de Physique des Gaz et des PlasmasUniversitéParis-SaclayOrsay 91405France State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The treatment and disposal of radioactive waste are presently facing great *** ion exchange resins have become a focus of attention due to their high production and serious environmental *** this paper,a simplified model of cationic exchange resin is proposed,and the degradation processes of cationic resin monomer initiated by hydroxyl radicals(·OH)are clarified by combining statistical molecular fragmentation(SMF)model and density functional theory(DFT)*** prediction of active sites indicates that the S-O bonds and the C-S bond of the sulfonic group are more likely to react during the *** meta-position of the sulfonic group on the benzene ring is the most active site,and the benzene ring without the sulfonic group has a certain *** C11-C14 and C17-C20 bonds,on the carbon skeleton,are the most easily *** is also found that dihydroxy addition and elimination reactions play a major role in the process of desulfonation,carbon skeleton cleavage and benzene ring *** decomposition mechanisms found through the combination of physical models and chemical calculations,provide theoretical guidance for the treatment of complex polycyclic aromatic hydrocarbons.

关键词： Cationic exchange resin Statistical molecular fragmentation model Density functional theory Hydroxyl radical Decomposition mechanism

Finite-temperature ductility-brittleness and electronic structures of Al_nSc（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 University School of Metallurgy Northeastern University Rare Earth Functional Materials (Xiong'an) Innovation Center Co. Ltd. laboratoire d'étude des Microstructures et de Mécanique des Matériaux (LEM3) Unikersité de Lorraine

Finite-temperature ductility-brittleness and electronic structures of Al3Sc,Al2Sc and AlSc are studied comparatively by first-principles calculations and ab initio molecular *** show that Al3Sc and Al2Sc 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 Al3Sc,Al2Sc 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

Black hole shadows in Einstein-Bel-Robinson gravity

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Chinese Physics C 2024年第5期48卷 272-283页

作者： B.Hamil B.C.Lütfüoğlu laboratoire de Physique Mathématique et Subatomique Facultédes Sciences ExactesUniversitéConstantine 1ConstantineAlgeria Department of Physics University of Hradec KrálovéRokitanského 6250003 Hradec KrálovéCzechia

Gravity models given by higher-order scalar curvature corrections are believed to bear important consequences. Einstein-Bel-Robinson (EBR) gravity with quartic curvature modification motivated Sajadi et al. to explore static spherically symmetric black hole solutions using perturbative methods. In this study, inspired by their work, we investigate AdS black hole shadows in EBR gravity and demonstrate how the gravity parameter alters the energy emission rate. Finally, we address the same problem in the presence of plasma, because the black holes are thought to be surrounded by a medium that changes the geodesic of photons.

关键词： black hole shadows Einstein-Bel-Robinson gravity plasma

Geochemistry, mineral paragenesis and geothermal conditions of oreforming fluids from the Ain El Bey Cu–Fe deposit: potential occurrence of native gold and precious metal traces (North African orogenic belt, Northern Tunisia)

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Acta Geochimica 2024年第2期43卷 366-384页

作者： Rania Ben Aissa Wiem Ben Aissa Said Tlig Lassaad Ben Aissa Abdessalem Ben Haj Amara Faculty of Science of Bizerte University of Carthage7021 ZarzounaBizerteTunisia laboratoire de Recherche Ressources Materiaux et EcosystemesUniversity of Carthage7021 ZarzounaBizerteTunisia Department of Geology University Claude Bernard Lyon 169622 VilleurbanneFrance Faculty of Science of Tunis University of Tunis-El ManarRommana1068 TunisTunisia

The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petromineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. Scanning Electron Microscope--Energy Dispersive Spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores(tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 ℃ for phase Ⅲ, from 254 to 350 ℃ for phase Ⅳ, and from 200 to 300 ℃ for phases Ⅴ and Ⅵ. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature(etal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary.

关键词： Ore-formingﬂuids Mineral geochemistry Mineral geothermometers Native silver-gold Ain El Bey Ore deposit North Tunisia

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

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

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