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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

sweetener and Flavor Enhancer Food Additives in Industrial Food Products Marketed in dakar: Frequency and diversity

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Open Journal of Applied sciences 2024年第1期14卷 101-117页

作者： Alé Kane Alioune sow Ndèye Adiara Ndiaye Coumba Gueye sagna Papa Amadou diakhaté Mady Cissé Amadou diop laboratoire des sciences Biologiques Agronomiques Alimentaires et de Modélisation des Systèmes Complexes (LABAAM) Université Gaston Berger (UGB) Saint-Louis Senegal département des Technologies Agroalimentaires|UFR des sciences Agronomiques de l’Aquaculture et des Technologies Alimentaires (S2ATA) Saint-Louis Senegal Ecole supérieure Polytechnique (EsP) Dakar Senegal laboratoire de chimie analytique et bromatologie UCAD Dakar Senegal

sweeteners and flavor enhancers are food additives widely used in industry, respectively, to add sweetness and flavor to foods. However, the presence of these substances is often criticized by consumers for their effects on health. What’s more, some scientific studies link these substances to certain pathologies. To guarantee food safety, competent authorities should have food standards based on risk analysis using consistent, reliable data. However, in developing countries, such data is often weak or non-existent. The aim of this study is therefore to carry out a pilot survey to establish the profile of sweeteners and flavour enhancers present in industrial food products marketed in senegal. The methodology consisted of sampling various food products sold on the senegalese market, based on analysis of labels containing information on ingredients, including additives. The investigation involved nine stores, one supermarket and 5 mini-markets in dakar. The results showed the presence of 6 taste enhancers in food products, the most frequent being sodium L-monoglutamate (E621), inosinate (E631) and disodium guanylate (E627). solid broths are the foodstuffs with the highest number of taste exhalters. As for sweeteners, 12 substances were identified, the most frequent being acesulfame potassium (E950), aspartame (E951), sucralose (E955) and saccharin (E954). Given the potential health risks associated with the consumption of these food additives, their control and monitoring on the market should be a priority for the competent authorities.

关键词： Exhalter sugar Acesulfame Potassium sodium Monoglutame Artificial Health Risk

Coupling Aquaculture—Crop Productions and Using of Water drained from Ponds Rearing Clarias gariepinus as Fertilizer for Okra Production (Abelmoschus esculentus var. Clemson spineless, L. Moench)

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Open Journal of Applied sciences 2024年第9期14卷 2628-2647页

作者： Louis dossou Magblénou Justin Kantoussan César Bassène dieynaba Yacine Mar Gueye Hamath sy laboratoire des sciences Biologiques Agronomiques et de Modlisation des Systmes Complexes (LaBAM) UFR des Sciences Agronomiques de lAquaculture et des Technologies Alimentaires (UFR S2ATA) Dpartement Aquaculture Universit Gaston Berger (UGB) Saint-Louis Senegal laboratoire des sciences Biologiques Agronomiques et de Modlisation des Systmes Complexes (LaBAM) UFR des Sciences Agronomiques de lAquaculture et des Technologies Alimentaires (UFR S2ATA) Dpartement Productions Vgtales et Agronomie (PVA) Universit Gaston Berger (UGB) Saint-Louis Senegal

The present study concerns the revalorization of drained water from aquaculture ponds rearing Clarias gariepinus on okra crops. The rearing was carried out at the farm of Gaston Berger University in 100 m2 ponds. In each pond, the individuals of C. garipinus with an average weight of 6 ± 0.3 g were stocked at a density of 11 per m2. The water temperature and pH were measured during the experiment. The control fishing is carried out every month to monitor variations in the weight and size of reared individuals. The plant production is carried out in elementary plots measuring 3 m × 1.5 m. Each plot was fertilized with either: drained water from C. gariepinus rearing (dWC), poultry droppings (Pd), cow dung (Cd) and mineral fertilizer (NPK). Treatments are carried out in tripliqua with either river water (RW), RW + the recommended dose of NPK (Rd-NPK), RW + Rd-Pd, RW + Rd-Cd, dWC, dWC + 25% Rd-NPK, dWC + 50% Rd-NPK, dWC + 75% Rd-NPK, dWC + 25% Rd-Pd, dWC + 50% Rd-Pd, dWC + 75% Rd-Pd, dWC + 25% Rd-Cd, dWC + 50% Rd-Cd, dWC + 75% Rd-Cd. Growth parameters and yield of okra were determined. The average temperature in the rearing environment was 27.6 ± 1.5˚C and pH 7.9 ± 1.1. After six (06) months of rearing, C. gariepinus individuals reached an average weight of 850.12 ± 1.3 g and an average height of 52.44 ± 1.1 cm. The daily weight gain and specific growth rates over this period were 3.9 g per day and 2.8% per day, respectively. The treatment T1 (RW + dR-NPK) gave the highest mean collar diameter and mean plant height with 2.3 ± 0.9 cm and 61.6 ± 32 cm, respectively. In T4 (dWC), the mean height of plants was 38.8 ± 23.5 cm and mean collar diameter 1.4 ± 0.8 cm. The growth performance in T4 was comparable to that of Rd-Cd (T3), but different from Rd-NPK (T1) and Rd-Pd (T2). The highest average number, average weight, average length and average diameter of fruits were noted in treatments T13 (RW + Rd-75%Cd) and T7 (dWC + 75% Rd-NPK). The best yields were noted in T1 (RW +

关键词： Integrated Aquaculture drained Water Fertilization C. gariepinus Okra

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

A global analysis of the introduction pathways and characteristics associated with non-native fish species introduction, establishment, and impacts

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Ecological processes 2024年第2期13卷 16-31页

作者： Camille Bernery Céline Bellard Franck Courchamp sébastien Brosse Boris Leroy CNRs Agro Paris Tech Ecologie Systématique Evolution Université Paris-Saclay Unité Biologie des Organismes et Ecosystèmes Aquatiques (BOREA UMR 8067) Muséum National d’Histoire Naturelle Sorbonne Universités Université de Caen Normandie Université des Antilles CNRS IRD laboratoire évolution & diversité Biologique (EdB UMR5174) Université Paul Sabatier-Toulouse 3 CNRS IRD UPS

Background The invasion success of introduced freshwater fishes is influenced by many factors, including ecological, species, and socioeconomic characteristics. Most studies that document the importance of these characteristics are conducted at local scales and/or focus on a single step of the invasion process. In this study, we aim to determine the species characteristics, ecological characteristics, and socioeconomic characteristics of non-native freshwater fish invasions. Our assessment was done at the global scale and considers all three steps of the invasion(i.e., introduction, establishment, and impact). For this purpose, we applied generalized linear models to 20 variables collected for 307 non-native species and modeled them as a function of ecological characteristics(i.e., environmental features), species traits(i.e., functional and morphological), and socioeconomic characteristics(i.e., human use and introduction pathways). We considered the number of countries in which each species was introduced, established, or had ecological impacts as a proxy of invasion step success. We also explored the specifics of species introduced through the aquaculture and the ornamental fish trade *** We found that non-native freshwater fishes with broad diets, high parental care, and multiple introduction pathways are the most widely introduced and established worldwide. The number of countries with impacts reported was best explained by the type of introduction pathway(i.e., aquaculture or fisheries). Moreover, among non-native species introduced through aquaculture, those belonging to Cypriniformes and having broad diets were the most widely introduced and established species. In contrast, the species introduced through the ornamental fish trade pathway belonged to various taxonomic orders but were mainly native to tropical *** Considering several types of factors is important when analyzing the invasion success of freshwater fish and disentang

关键词： Aquaculture Ecology Exotic Freshwater fish Introduction pathway Invasion step Morphology Ornamental fish trade socioeconomic Trait

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

Fast synthesis of gold nanoparticles by cold atmospheric pressure plasma jet in the presence of Au^(+) ions and a capping agent

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Plasma science and Technology 2024年第7期26卷 108-115页

作者： Tatiana HABIB José Mauricio A.CAIUT Bruno CAILLIER laboratoire diagnostics des Plasmas Hors Equilibre(dPHE) Universitéde ToulouseINU ChampollionAlbi 81000France department of Chemistry The Nanomaterials and Luminescent Systems GroupFaculty of PhilosophyScience and Letters at Ribeirão PretoUniversity of São PauloRibeirão Preto-SP 14040-901Brazil

Homogeneous gold nanoparticles were synthesized under atmospheric pressure using a nonthermal helium plasma jet in a single-step process.A current power supply was used to generate the plasma discharge rich in diverse reactive *** species induce rapid chemical reactions responsible for the reduction of the gold salts upon contact with the liquid *** this study,spherical and monodispersed gold nanoparticles were obtained within 5 min of plasma exposure using a solution containing gold(Ⅲ)chloride hydrate(HAuCl_(4))as a precursor and polyvinylpyrrolidone(PVP)as a capping agent to inhibit *** formation of these metal nanoparticles was initially perceptible through a visible change in the sample's color,transitioning from light yellow to a red/pink *** was subsequently corroborated by UVvis spectroscopy,which revealed an optical absorption in the 520-550 nm range for Au NPs,corresponding to the surface plasmon resonance(sPR)*** investigation into the impact of various parameters,including plasma discharge duration,precursor and capping agent concentrations,was carried out to optimize conditions for the formation of well-separated,spherical gold *** light scattering(dLs)was used to measure the size of these nanoparticles,transmission electron microscopy(TEM)was used to observe their morphology and X-ray diffraction(XRd)was also employed to determine their crystallographic *** results confirm that homogeneous spherical gold nanoparticles with an average diameter of 13 nm can be easily synthesized through a rapid,straightforward,and environmentally friendly approach utilizing a helium atmospheric pressure plasma.

关键词： gold nanoparticles non-thermal plasma jet helium dBd

Photovoltaic waste management in sub-saharan Africa:current practices in Burkina Faso

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Waste disposal and sustainable Energy 2024年第2期6卷 271-282页

作者： Kodami Badza Yrebegnan Moussa soro Marie sawadogo laboratoire Energies Renouvelables et EfficacitéEnergétique Institut International d'Ingenierie de I'Eau et de I'Environnement(2iE)01 BP 594 OuagadougouBurkina Faso

sub-saharan Africa is witnessing a proliferation of photovoltaic(PV)waste due to the increasing number of solar PV power *** waste(panels,batteries,electrical cables,mounting structures,and inverters)consists of elements such as mercury,cadmium,chromium,lead,copper,aluminum,fluorinated compounds,and plastics that are toxic to human health and the environment if a proper management system is not *** many studies worldwide have focused on PV waste management,very few have been conducted in sub-saharan *** study aims to investigate the current PV waste management system in Burkina Faso,determine stakeholder profiles,and propose strategies to enhance the existing *** research,interviews,questionnaires,and field visits were used in the *** survey showed that young people,mainly under 30 years of age and with a primary education,dominate(70%)in terms of PV waste collection and repair activities,while the more technical recycling and export activities are carried out mainly(88%)by stakeholders older than 40 years and with a secondary education(60%).Among the older stakeholders,100%are aware of the hazardous nature of PV waste,whereas 36%are young *** an environmental perspective,the main source of contamination observed is the release of lead-rich sulfuric acids into water and soil during the collection and repair *** the recycling of batteries and electrical cables,toxic fumes are emitted into the air,and recycling residues rich in toxic substances are *** reduce risks to human health and the environment when managing PV waste,the introduction of legislation,the multiplication of collection points and appropriate infrastructures,the training and awareness-raising of stakeholders,and the extended responsibility of manufacturers are *** on the economic feasibility of setting up formal management structures are needed to complete this work.

关键词： Photovoltaic waste sub-saharan Africa Waste management Recycling Batteries Incineration

determinants of saturation magnetic flux density in Fe-based metallic glasses: insights from machine-learning models

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Rare Metals 2024年第10期43卷 5256-5267页

作者： Jie Xiong Bo-Wen Bai Hao-Ran Jiang Angeles Faus-Golfe Materials Genome Institute Shanghai University Institute of special Environments Physical sciences Harbin Institute of Technology laboratoire de Physique des 2 Infinis Irene Joliot-Curie (IJCLab) CNRS-IN2P3Universite′Paris-Saclay

Fe-based metallic glasses have garnered significant attention due to their low coercivity force and core loss. Enhancing the saturation magnetic flux density(Bs) of Fe-based metallic glasses is crucial for their industry applications. This work constructed a dataset comprising330 training data and 157 test data. The support vector regression model surpassed the tree-based ensemble models in the test set and demonstrated comparable accuracy to the tree-based ensemble models in the training set. Additionally, we proposed an indicator for Bsbased on symbolic regression. This newly proposed indicator exhibits a Pearson correlation coefficient exceeding 0.92 with Bs. The present work provides a simple and accurate formula for predicting the Bsof Fe-based amorphous alloys, demonstrating the effectiveness of machine learning approaches in discovering novel soft magnetic materials.

关键词： Fe-based metallic glasses Machine learning saturation magnetic flux density symbolic regression