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101. Workforce planning and production scheduling in a reconfigurable manufacturing system facing the COVID-19 pandemic

Author

Behdin, Vahedi-Nouri, Reza, Tavakkoli-Moghaddam, Zdeněk, Hanzálek, Alexandre, Dolgui, School of Industrial Engineering [Tehran], College of Engineering [Tehran], University of Tehran-University of Tehran, Czech Technical University in Prague (CTU), Département Automatique, Productique et Informatique (IMT Atlantique - DAPI), IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Modélisation, Optimisation et DEcision pour la Logistique, l'Industrie et les Services (LS2N - équipe MODELIS), Laboratoire des Sciences du Numérique de Nantes (LS2N), Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-École Centrale de Nantes (Nantes Univ - ECN), Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Nantes Université (Nantes Univ), and This work was supported by the European Regional DevelopmentFund under the project AI&Reasoning (reg. no. CZ.02.1.01/0.0/0.0/15_003/0000466).

Subjects
Hardware and Architecture, Control and Systems Engineering, [INFO.INFO-AU]Computer Science [cs]/Automatic Control Engineering, [INFO]Computer Science [cs], [INFO.INFO-RO]Computer Science [cs]/Operations Research [cs.RO], Industrial and Manufacturing Engineering, Software
Abstract

International audience; Due to the outbreak of the COVID-19 pandemic, the manufacturing sector has been experiencing unprecedentedissues, including severe fluctuation in demand, restrictions on the availability and utilization of the workforce,and governmental regulations. Adopting conventional manufacturing practices and planning approaches undersuch circumstances cannot be effective and may jeopardize workers’ health and satisfaction, as well as thecontinuity of businesses. Reconfigurable Manufacturing System (RMS) as a new manufacturing paradigm hasdemonstrated a promising performance when facing abrupt market or system changes. This paper investigates ajoint workforce planning and production scheduling problem during the COVID-19 pandemic by leveraging theadaptability and flexibility of an RMS. In this regard, workers’ COVID-19 health risk arising from their allocation,and workers’ preferences for flexible working hours are incorporated into the problem. Accordingly, first, novelMixed-Integer Linear Programming (MILP) and Constraint Programming (CP) models are developed to formulatethe problem. Next, exploiting the problem’s intrinsic characteristics, two properties of an optimal solution areidentified. By incorporating these properties, the initial MILP and CP models are considerably improved. Af-terward, to benefit from the strengths of both improved models, a novel hybrid MILP-CP solution approach isdevised. Finally, comprehensive computational experiments are conducted to evaluate the performance of theproposed models and extract useful managerial insights on the system flexibility.

Published
2022
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102. Tappeh Qazanchi, an example of a pioneering farming community during the Pre-Pottery Neolithic in Central Zagros (Iran). In session: Uses and misuses of landscapes and resources: New perspectives on pioneer farming societies in the world

Author

Mashkour, M., Davoudi, H., Tengberg, M., Mylona, P., Shidrang, S., Djamali, M., Beizaee Doost, S., Khazaeli, R., Fathi, H., Archéozoologie, archéobotanique : sociétés, pratiques et environnements (AASPE), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Archaeozoological section, Bioarchaeological laboratory, University of Tehran, Muséum national d'Histoire naturelle (MNHN), National Museum of Iran, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), University of Tehran, Central Laboratory, Bioarchaeology Laboratory, LIA-CNRS project HAOMA - Human and Environment Interaction on the Iranian Plateau. PIs Marjan Mashkour (CNRS-AASPE) & Morteza Djamali (CNRS-IMBE), and AFEQ-CNF INQUA https://q13.sciencesconf.org

Subjects
[SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

International audience; Recent archaeological investigations in the North West of Kermanshah have highlighted the importance of this region for documenting initial stages of the Neolithisation of Central Zagros. During winter 2019 we excavated Tappeh Qazānchi, near Kermanshah. The site was first reported by Robert J. Braidwood during the 60’s. It is unfortunately now heavily damaged by agricultural activities. Tappeh Qazānchi is a 2 hectares mound of 13 meters height, 160 meters long and 160 meters wide. Our preliminary surface collection on the site during 2012 indicated a multi-period occupation and the presence of lithic tools characteristic of the Early Neolithic period. The 2019 sounding confirmed these preliminary observations. We opened three trenches and found a Bronze Age deposit on the top of the mound and pre-pottery Neolithic ashy layers from eight to thirteen meters lower down. The Neolithic occupation of Tappeh Qazānchi is comparable to Chogha Golan, Sheikhi Abad and East Chia Sabz on the basis of radiocarbon dating and lithic analyses. This presentation will summarise the results of chronological, bioarchaeological, lithic and micromorphological studies with a particular emphasis on archaeobotanical, archaeozoological and micromorphologial results.

Published
2022

103. Phenotypic and Molecular-Phylogenetic Analyses Reveal Distinct Features of Crown Gall-Associated Xanthomonas Strains

Author

Hamzeh Mafakheri, S. Mohsen Taghavi, Sadegh Zarei, Touraj Rahimi, Mohammad Sadegh Hasannezhad, Perrine Portier, Marion Fischer-Le Saux, Ivica Dimkić, Ralf Koebnik, Nemanja Kuzmanović, Ebrahim Osdaghi, Shiraz University (Shiraz University ), University of Tehran, Islamic Azad University, University of Applied Science and Technology (UAST), Institut de Recherche en Horticulture et Semences (IRHS), Université d'Angers (UA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Rennes Angers, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), University of Belgrade [Belgrade], Plant Health Institute of Montpellier (UMR PHIM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de Montpellier (UM), Julius Kühn-Institut - Federal Research Centre for Cultivated Plants (JKI), Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), Project number 429677233, Ministry of Education, Science and Technological Development of the Republic of Serbia, INTERREG ADRION OIS-AIR (Open Innovation System of the Adriatic-Ionian Region) proof-of-concept project for the financial support of his research (contracts 451-03-9/2021-14/200178 and OIS-AIR 77)., Iranian Ministry of Science and Technology for a 6-month fellowship at the University of Tehran, Iran., and European Project

Subjects
weeping fig, Microbiology (medical), General Immunology and Microbiology, Ecology, Physiology, clade I Xanthomonas, food and beverages, Ficus benjamina, Cell Biology, [SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology, [SDV.BV.PEP]Life Sciences [q-bio]/Vegetal Biology/Phytopathology and phytopharmacy, T3SS, [SDV.GEN.GPL]Life Sciences [q-bio]/Genetics/Plants genetics, Infectious Diseases, Agrobacterium sp, Genetics, Amaranthus sp
Abstract

International audience; In summer 2019, widespread occurrence of crown gall disease caused byAgrobacterium spp. was observed on commercially grown ornamental plants in south-ern Iran. Beside agrobacteria, pale yellow-pigmented Gram-negative strains resemblingthe members of Xanthomonas were also associated with crown gall tissues on weep-ing fig (Ficus benjamina) and Amaranthus sp. plants. The purpose of the present studywas to characterize the crown gall-associated Xanthomonas strains using plant inocula-tion assays, molecular-phylogenetic analyses, and comparative genomics approaches.Pathogenicity tests showed that the Xanthomonas strains did not induce diseasesymptoms on their host of isolation. However, the strains induced hypersensitive reac-tion on tobacco, geranium, melon, squash, and tomato leaves via leaf infiltration.Multilocus sequence analysis suggested that the strains belong to clade IA ofXanthomonas, phylogenetically close to Xanthomonas translucens, X. theicola, and X.hyacinthi. Average nucleotide identity and digital DNA-DNA hybridization valuesbetween the whole-genome sequences of the strains isolated in this study and refer-ence Xanthomonas strains are far below the accepted thresholds for the definition ofprokaryotic species, signifying that these strains could be defined as two new specieswithin clade IA of Xanthomonas. Comparative genomics showed that the strains iso-lated from crown gall tissues are genetically distinct from X. translucens, as almost allthe type III secretion system genes and type III effectors are lacking in the formergroup. The data obtained in this study provide novel insight into the breadth ofgenetic diversity of crown gall-associated bacteria and pave the way for research ongall-associated Xanthomonas-plant interactions.

Published
2022
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104. Optimal Corrective Maintenance Policy Encountering Competing Risks Using Machine Learning Algorithms

Author

Misaii, Hasan, Fouladirad, Mitra, Haghighi, Firoozeh, MISAII, HASAN, College of Science of the University of Tehran (UT College of Science), Laboratoire Informatique et Société Numérique (LIST3N), Université de Technologie de Troyes (UTT), Laboratoire Modélisation et Sûreté des Systèmes (LM2S), Université de Technologie de Troyes (UTT)-Université de Technologie de Troyes (UTT), School of Mathematics, Statistics and Computer Science [Tehran], University of Tehran, and Dublin, Ireland

Subjects
[SPI]Engineering Sciences [physics], Machine Learning Algorithms, Maintenance Optimization, [MATH.MATH-ST]Mathematics [math]/Statistics [math.ST], Non-parametric and Parametric Estimation, [SPI] Engineering Sciences [physics], [MATH.MATH-ST] Mathematics [math]/Statistics [math.ST]
Abstract

International audience; In this paper, a series system is considered which is periodically inspected. At inspection times, the failed componentsare replaced by a new one. Therefore, from the component point of view, maintenance is perfect and from thesystem point of view, maintenance is imperfect. Three different scenarios related to the components lifetimedistribution are considered. Firstly, the lifetime distribution of the components and their parameters are assumedto be known, secondly, the lifetime distributions are assumed to be known with unknown parameters and, thirdlylifetime distributions are considered to be unknown. A cost-based maintenance optimization is carried out. Theinspection interval is the decision parameter in all scenarios. The first scenario is considered as a benchmark toother scenarios. For the second and third scenarios, machine learning algorithms are used to estimate the decisionparameter and to derive the long-run average total maintenance cost. Different cases are compared through numericalimplementations.

Published
2022

105. Randomized source sketching for full waveform inversion

Author

Hossein S. Aghamiry, Ali Gholami, Kamal Aghazade, Stéphane Operto, Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Institute of Geophysics, University of Tehran, University of Tehran, and Institut de Géophysique, Université de Téhéran, Iran

Subjects
Partial differential equation, Series (mathematics), Deterministic algorithm, Computer science, 0211 other engineering and technologies, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, FOS: Physical sciences, 02 engineering and technology, Inverse problem, Regularization (mathematics), Geophysics (physics.geo-ph), Reduction (complexity), Physics - Geophysics, Mathematics - Analysis of PDEs, Dimension (vector space), [SDU]Sciences of the Universe [physics], Convergence (routing), FOS: Mathematics, General Earth and Planetary Sciences, Electrical and Electronic Engineering, Algorithm, Analysis of PDEs (math.AP), 021101 geological & geomatics engineering
Abstract

International audience; Partial differential equation (PDE) constrained optimization problems such as seismic full waveform inversion (FWI) frequently arise in the geoscience and related fields. For such problems, many observations are usually gathered by multiple sources, which form the right-hand-sides of the PDE constraint. Solving the inverse problem with such massive data sets is computationally demanding, in particular when dealing with large number of model parameters.This paper proposes a novel randomized source sketching method for the efficient resolution of multisource PDE constrained optimization problems.We first formulate the different source-encoding strategies used in seismic imaging into a unified framework based on a randomized sketching. To this end, the source dimension of the problem is projected in a smaller domain by a suitably defined projection matrix that gathers the physical sources in super-sources through a weighted summation. This reduction in the number of physical sources decreases significantly the number of PDE solves while suitable sparsity-promoting regularization can efficiently mitigate the footprint of the cross-talk noise to maintain the convergence speed of the algorithm. We implement the randomized sketching method in an extended search-space formulation of frequency-domain FWI, which relies on the alternating-direction method of multipliers (ADMM). Numerical examples carried out with a series of well-documented 2D benchmarks demonstrate that the randomized sketching algorithm reduces the cost of large-scale problems by at least one order of magnitude compared to the original deterministic algorithm.

Published
2021
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106. Maintenance in Presence of Incomplete Data in Series Systems

Author

Misaii, Hasan, Firoozeh, Haghighi, Fouladirad, Mitra, School of Mathematics, Statistics and ComputerScience, College of Science, University of Tehran, Tehran, 14155-6455, Iran, College of Science of the University of Tehran (UT College of Science), Laboratoire Modélisation et Sûreté des Systèmes (LM2S), Laboratoire Informatique et Société Numérique (LIST3N), Université de Technologie de Troyes (UTT)-Université de Technologie de Troyes (UTT), and 7th Seminar on Reliability and its Applications

Subjects
[STAT]Statistics [stat], [SPI]Engineering Sciences [physics], Masking, Maintenance optimization, Incomplete data
Abstract

International audience; Maintenance optimization problems have received much attention recently. Applying optimization actions in different contexts leads to encounter expected and unexpected challenges. Inspections and monitoring make useful data for optimizing maintenance policies and collected data play an especial role in such problems. But sometimes data are incomplete. In this paper, masking will be discussed in terms of the incompleteness of data.

Published
2021

107. The first archaeological campaign at Tappeh Qazānchi, a new PPN site in the West Central Zagros

Author

Mashkour, Marjan, Davoudi, Hossein, Shidrang, S, Orange, M., Khoramli, F., Mylona, P, Djamali, M., Tengberg, Margareta, Rahmati, M., Beyzaei Doust, Sanaz, Moradi, B., Khazaeli, R., Fathi, Homa, Fathi, Z., Archéozoologie, archéobotanique : sociétés, pratiques et environnements (AASPE), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), University of Tehran, Central Laboratory, Bioarchaeology Laboratory, Center for Paleolithic Research, National Museum of Iran, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Archaeozoological section, Bioarchaeological laboratory, University of Tehran, and Université de Copenhague

Subjects
[SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory
Abstract

International audience

Published
2021

108. About the unification type of modal logic K5 and its extensions

Author

Alizadeh, Majid, Ardeshir, Mohammad, Balbiani, Philippe, Mojtahedi, Mojtaba, School of Mathematics, Statistics and Computer Science, College of Science, University of Tehran, Iran, College of Science of the University of Tehran (UT College of Science), Department of Mathematical Sciences, Sharif University of Technology, Sharif University, Sharif University of Technology [Tehran] (SUT), Logique, Interaction, Langue et Calcul (IRIT-LILaC), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
[INFO.INFO-LO]Computer Science [cs]/Logic in Computer Science [cs.LO]
Published
2021

111. Nutraceuticals and Superfoods

Author

Mohammadian, Mehdi, Salami, Maryam, Moghadam, Maryam, Emam-Djomeh, Zahra, Moosavi-Movahedi, Ali Akbar, University of Tehran, and Moosavi-Movahedi, Ali Akbar

Published
2021
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121. A Brief History of Collage

Author

Adibi, Ali Asghar, University of Tehran, Adibi, Ali Asghar, Jafari, Ali Yaser, Translated by, and Khorramrouei, Reihaneh, Translated by

Published
2021
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122. ADMM-based full-waveform inversion for microseismic imaging

Author

Ali Gholami, Hossein S. Aghamiry, Stéphane Operto, Alison Malcolm, Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Institute of Geophysics, University of Tehran, and University of Tehran

Subjects
Optimization problem, Microseism, 010504 meteorology & atmospheric sciences, Underdetermined system, Computer science, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Inverse transform sampling, Strong prior, Inversion (meteorology), 010502 geochemistry & geophysics, 01 natural sciences, Noise, Geophysics, Optimization and Control (math.OC), [SDU]Sciences of the Universe [physics], Geochemistry and Petrology, FOS: Mathematics, Focus (optics), Algorithm, Mathematics - Optimization and Control, 0105 earth and related environmental sciences
Abstract

SUMMARYFull waveform inversion (FWI) is beginning to be used to characterize weak seismic events at different scales, an example of which is microseismic event (MSE) characterization. However, FWI with unknown sources is a severely underdetermined optimization problem, and hence requires strong prior information about the sources and/or the velocity model. The frequency-domain wavefield reconstruction inversion (WRI) method has shown promising results to mitigate the non-linearity of the FWI objective function generated by cycle-skipping. WRI relies on the reconstruction of data-assimilated wavefields, which approach the true wavefields near the receivers, a helpful feature when the source is added as an additional optimization variable. We present an adaptation of a recently proposed version of WRI based on the alternating direction method of multipliers that first finds the location of the MSEs and then reconstructs the wavefields and the source signatures jointly. Finally, the subsurface model is updated to focus the MSEs at their true locations. The method does not require prior knowledge of the number of MSEs. The inversion is stabilized by sparsifying regularizations separately tailored to the source location and velocity model subproblems. The method is tested on the Marmousi model using one MSE and two clusters of MSEs with two different initial velocity models, an accurate one and a rough one, as well as with added noise. In all cases, the method accurately locates the MSEs and recovers their source signatures.

Published
2021
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123. Friction stir welding/processing of metals and alloys: A comprehensive review on microstructural evolution

Author

Philip J. Withers, Amir Mostafaei, Rustam Kaibyshev, Adrian P. Gerlich, Joseph D. Robson, Aude Simar, Gürel Çam, Farzad Khodabakhshi, Alexis Deschamps, Akbar Heidarzadeh, David P. Field, Sergey Mironov, Azarbaijan Shahid Madani University, Belgorod National Research University, Iskenderun Technical University, Université Catholique de Louvain = Catholic University of Louvain (UCL), University of Waterloo [Waterloo], University of Tehran, Illinois Institute of Technology (IIT), Washington State University (WSU), University of Manchester [Manchester], Science et Ingénierie des Matériaux et Procédés (SIMaP), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Mühendislik ve Doğa Bilimleri Fakültesi -- Makina Mühendisliği Bölümü, Çam, Gürel, Azarbaijan Shahid Madani University - Department of Materials Engineering, Belgorod National Research University - n/a, Iskenderun Technical University - Department of Mechanical Engineering, UCL - SST/IMMC/IMAP - Materials and process engineering, University of Waterloo - Department of Mechanical and Mechatronics Engineering, University of Tehran - School of Metallurgy and Materials Engineering, Illinois Institute of Technology - Department of Mechanical, Materials and Aerospace Engineering, Washington State University - School of Mechanical and Materials Engineering, The University of Manchester - Department of Materials, Université Grenoble-Alpes - CNRS,Grenoble INP, SIMaP, and The University of Manchester - Henry Royce Institute, Department of Materials

Subjects
Friction stir processing, Friction stir welding, Welded Joints, Intermetallic, Stacking fault energy, 02 engineering and technology, Welding, 01 natural sciences, law.invention, Intermetallic compound layer, Bobbins, Recovery, law, Dissimilar material joints, General Materials Science, Microstructure, ComputingMilieux_MISCELLANEOUS, 010302 applied physics, Multidisciplinary, Austenitic stainless-steel, Strain rate, High strain rates, Textures, Metals and alloys, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, In-situ nanocomposite, Metallurgy, Aluminum-matrix composites, Joint performance, 0210 nano-technology, Materials science, Friction, Welds, Materials Science, Tool rotational speed, Context (language use), Processing, Research laboratories, Friction stir welding(FSW), Metallic matrix composites, Az31 magnesium alloy, 0103 physical sciences, Processing parameters, Friction stir welding/processing, High-entropy alloy, Welded dissimilar joints, Joint (geology), Microstructural evolution, Precipitation (chemistry), Continuous dynamic recrystallization, Microstructural control, Recrystallization, Al-mg alloy, Metal matrix composites
Abstract

The unique combination of very large strains, high temperatures and high strain rates inherent to friction stir welding (FSW) and friction stir processing (FSP) and their dependency on the processing parameters provides an opportunity to tailor the microstructure, and hence the performance of welds and surfaces to an extent not possible with fusion processes. While a great deal of attention has previously been focused on the FSW parameters and their effect on weld quality and joint performance, here the focus is on developing a comprehensive understanding of the fundamentals of the microstructural evolution during FSW/P. Through a consideration of the mechanisms underlying the development of grain structures and textures, phases, phase transformations and precipitation, microstructural control across a very wide range of similar and dissimilar material joints is examined. In particular, when considering the joining of dissimilar metals and alloys, special attention is focused on the control and dispersion of deleterious intermetallic compounds. Similarly, we consider how FSP can be used to locally refine the microstructure as well as provide an opportunity to form metal matrix composites (MMCs) for near surface reinforcement. Finally, the current gaps in our knowledge are considered in the context of the future outlook for FSW/P.

Published
2021
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124. Wolbachia manipulate fitness benefits of olfactory associative learning in a parasitoid wasp

Author

Ahmad Ashouri, Jean-Sébastien Pierre, Joan van Baaren, Hossein Kishani Farahani, Pouria Abroon, University of Tehran, Bu-Ali Sina University, Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), A grant from university of Tehran, Université de Rennes (UR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), and Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)

Subjects
0106 biological sciences, Fitness benefits, Physiology, Conditioning, Classical, Wasps, Zoology, Aquatic Science, 010603 evolutionary biology, 01 natural sciences, Aversive learning, Parasitoid wasp, 03 medical and health sciences, Memory, Associative learning, Memory span, Animals, Molecular Biology, Ecology, Evolution, Behavior and Systematics, 030304 developmental biology, 0303 health sciences, biology, Host (biology), fungi, Trichogramma brassicae, biology.organism_classification, Fecundity, Attraction, Smell, [SDV.BA.ZI]Life Sciences [q-bio]/Animal biology/Invertebrate Zoology, Insect Science, Female, Animal Science and Zoology, Wolbachia, [SDV.EE.IEO]Life Sciences [q-bio]/Ecology, environment/Symbiosis
Abstract

Upon encountering a host, a female parasitoid wasp has to decide whether to learn positive or negative cues related to the host. The optimal female decision will depend on the fitness costs and benefits of learned stimuli. Reward quality is positively related to the rate of behavioral acquisition in processes such as associative learning. Wolbachia, an endosymbiotic bacterium, often plays an impressive role in the manipulation of its arthropod host's biology. Here, we studied the responses of two natural Wolbachia infected/uninfected Trichogramma brassicae wasp populations to theoretically high- and low-reward values during a conditioning process and the consequences of their responses in terms of memory duration. According to our results, uninfected wasps showed an attraction response to high-value rewards, but showed aversive learning in response to low-value rewards. The memory span of uninfected wasps after conditioning by low-value rewards was significantly shorter than that for high-value rewards. As our results revealed, responses to high-quality hosts will bring more benefits (bigger size, increased fecundity and enhanced survival) than those to low-quality hosts for uninfected wasps. Infected wasps were attracted to conditioned stimuli with the same memory duration after conditioning by both types of hosts. This was linked to the fact that parasitoids emerging from both types of hosts present the same life-history traits. Therefore, these hosts represent the same quality reward for infected wasps. According to the obtained results, it can be concluded that Wolbachia manipulates the learning ability of its host, resulting in the wasp responding to all reward values similarly.

Published
2021
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125. Poor adult nutrition impairs learning and memory in a parasitoid wasp

Author

Jean-Sébastien Pierre, Stéphane Kraus, Hossein Kishani Farahani, Mathieu Lihoreau, Yasaman Moghaddassi, Agronutrition, University of Tehran, Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut des sciences du cerveau de Toulouse. (ISCT), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J)-CHU Toulouse [Toulouse]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Agronutrition CO. (France), University of Tehran (Iran) University of Tehran, PhD CIFRE grant from Koppert, French National Agency of Research and Technology (ANRT) French National Research Agency (ANR), CNRS Centre National de la Recherche Scientifique (CNRS) European Commission, Agence Nationale de la RechercheFrench National Research Agency (ANR) European Commission [ANR-16-CE02-0002-01, ANR-19-CE37-0024, ANR-20-ERC8-0004-01], European Regional Development Fund European Commission [MP0021763-ECONECT], Agence de la Transition Ecologique (LOTAPIS), ANR-16-CE02-0002,POLLINET,Structure et efficacité des réseaux de pollinisation dans des environnements changeants(2016), ANR-19-CE37-0024,3DNaviBee,How do bees solve navigational challenges in 3D?(2019), ANR-20-ERC8-0004,BEE-MOVE,Pollination ecology: how do bees move across the landscape and fashion plant reproduction?(2020), Université de Rennes (UR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherches sur la Cognition Animale - UMR5169 (CRCA), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre de Biologie Intégrative (CBI), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Toulouse Mind & Brain Institut (TMBI), Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre de Biologie Intégrative (CBI), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Toulouse Mind & Brain Institut (TMBI), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Mathieu, Lihoreau, Structure et efficacité des réseaux de pollinisation dans des environnements changeants - - POLLINET2016 - ANR-16-CE02-0002 - AAPG2016 - VALID, Pollination ecology: how do bees move across the landscape and fashion plant reproduction? - - BEE-MOVE2020 - ANR-20-ERC8-0004 - T-ERC - VALID, and How do bees solve navigational challenges in 3D? - - 3DNaviBee2019 - ANR-19-CE37-0024 - AAPG2019 - VALID

Subjects
0106 biological sciences, Science, Wasps, Zoology, 010603 evolutionary biology, 01 natural sciences, Article, Learning and memory, Parasitoid wasp, Parasitoid, 03 medical and health sciences, [SCCO]Cognitive science, Animals, 030304 developmental biology, 2. Zero hunger, Memory Disorders, Larva, 0303 health sciences, Multidisciplinary, biology, Learning Disabilities, Host (biology), Malnutrition, fungi, Cognitive neuroscience, Cognition, Feeding Behavior, [SCCO] Cognitive science, Fecundity, biology.organism_classification, Associative learning, Odor, Feeding behaviour, Neuronal physiology, Medicine, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

Animals have evolved cognitive abilities whose impairment can incur dramatic fitness costs. While malnutrition is known to impact brain development and cognitive functions in vertebrates, little is known in insects, whose small brain appears particularly vulnerable to environmental stressors. Here, we investigated the influence of diet quality on learning and memory in the parasitoid wasp Venturia canescens. Newly emerged adults were exposed for 24h to either honey, sucrose solution 20%, sucrose solution 10%, or no food, before being conditioned in an olfactory associative learning task in which an odor (orange) was associated to a reward (host larvae). Wasps fed honey showed 3.5 times higher learning performances and 1.5 times longer memory retention times than wasps fed sucrose solutions and starved wasps. Poor diets also reduced longevity and fecundity. Our results demonstrate the importance of early adult nutrition for optimal cognitive function in these parasitoid wasps that must quickly develop olfactory memories for choosing high quality hosts for their progeny.

Published
2021
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126. Programme Paléoanthropologique Franco-Iranien - FIPP - Qaleh Kurd (Qazvin, Iran) et Mirak (Semnan, Iran). Bilan du Quadriennal 2018-2021

Author

Berillon, Gilles, Nasab, Hamed Vahdati, Kharazian, Mohammad Akhavan, Antoine, Pierre, Khaneghah, Asghar Asgari, Bahain, Jean-Jacques, Bonilauri, Stéphanie, Chapon-Sao, Cécile, Falguères, Christophe, Gallet, Xavier, Guérin, Guillaume, Hashemi, Seyyed Milad, Heydari, Maryam, Jamet, Guillaume, Nomade, Sébastien, Puaud, Simon, Sévêque, Noémie, Stoetzel, Emmanuelle, Tombret, Olivier, Zeitoun, Valéry, Berillon, Gilles, Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS), Tarbiat Modares University [Tehran], Université Paris 1 Panthéon-Sorbonne - UFR Géographie (UP1 UFR08), Université Paris 1 Panthéon-Sorbonne (UP1), Laboratoire de géographie physique : Environnements Quaternaires et Actuels (LGP), Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Institute of Research and Social Studies, Faculty of Social Sciences, University of Tehran, Tehran, Iran, University of Tehran, IRAMAT-Centre de recherche en physique appliquée à l’archéologie (IRAMAT-CRP2A), Institut de Recherches sur les Archéomatériaux (IRAMAT), Université de Technologie de Belfort-Montbeliard (UTBM)-Université d'Orléans (UO)-Université Bordeaux Montaigne (UBM)-Centre National de la Recherche Scientifique (CNRS)-Université de Technologie de Belfort-Montbeliard (UTBM)-Université d'Orléans (UO)-Université Bordeaux Montaigne (UBM)-Centre National de la Recherche Scientifique (CNRS), Institut national de recherches archéologiques préventives (Inrap), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), GeoArchEon SARL, Archéozoologie, archéobotanique : sociétés, pratiques et environnements (AASPE), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche en Paléontologie - Paris (CR2P), Muséum national d'Histoire naturelle (MNHN)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and CNRS - MNHN - Université Tarbiat Modares - Université de Téhéran

Subjects
[SHS] Humanities and Social Sciences, [SHS]Humanities and Social Sciences
Published
2021

127. Efficient extended-search space full-waveform inversion with unknown source signatures

Author

Stéphane Operto, Ali Gholami, F W Mamfoumbi-Ozoumet, Hossein S. Aghamiry, Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Institute of Geophysics, University of Tehran, and University of Tehran

Subjects
010504 meteorology & atmospheric sciences, Computer science, Degrees of freedom (statistics), Relaxation (iterative method), [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Inversion (meteorology), 010502 geochemistry & geophysics, Wave equation, 01 natural sciences, Geophysics, Operator (computer programming), Data assimilation, Geochemistry and Petrology, Robustness (computer science), [SDU]Sciences of the Universe [physics], Optimization and Control (math.OC), Direct methods, FOS: Mathematics, Sensitivity (control systems), Mathematics - Optimization and Control, Algorithm, 0105 earth and related environmental sciences
Abstract

SUMMARY Full waveform inversion (FWI) requires an accurate estimation of source signatures. Due to the coupling between the source signatures and the subsurface model, small errors in the former can translate into large errors in the latter. When direct methods are used to solve the forward problem, classical frequency-domain FWI efficiently processes multiple sources for source signature and wavefield estimations once a single lower–upper (LU) decomposition of the wave-equation operator has been performed. However, this efficient FWI formulation is based on the exact solution of the wave equation and hence is highly sensitive to the inaccuracy of the velocity model due to the cycle skipping pathology. Recent extended-space FWI variants tackle this sensitivity issue through a relaxation of the wave equation combined with data assimilation, allowing the wavefields to closely match the data from the first inversion iteration. Then, the subsurface parameters are updated by minimizing the wave-equation violations. When the wavefields and the source signatures are jointly estimated with this approach, the extended wave equation operator becomes source dependent, hence making direct methods and, to a lesser extent, block iterative methods ineffective. In this paper, we propose a simple method to bypass this issue and estimate source signatures efficiently during extended FWI. The proposed method replaces each source with a blended source during each data-assimilated wavefield reconstruction to make the extended wave equation operator source independent. Besides computational efficiency, the additional degrees of freedom introduced by spatially distributing the sources allows for a better signature estimation at the physical location when the velocity model is rough. We implement the source signature estimation with a variable projection method in the recently proposed iteratively refined wavefield reconstruction inversion (IR-WRI) method. Numerical tests on the Marmousi II and 2004 BP salt synthetic models confirm the efficiency and the robustness against velocity model errors of the new method compared to the case where source signatures are known.

Published
2021
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128. Robust wavefield inversion via phase retrieval

Author

Ali Gholami, Hossein S. Aghamiry, Stéphane Operto, Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Institute of Geophysics, University of Tehran, University of Tehran, Géoazur (GEOAZUR 6526), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA), Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (... - 2019) (UNS)

Subjects
Signal Processing (eess.SP), Computer science, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Inverse, 02 engineering and technology, 010502 geochemistry & geophysics, 01 natural sciences, Tikhonov regularization, Geochemistry and Petrology, FOS: Mathematics, FOS: Electrical engineering, electronic engineering, information engineering, 0202 electrical engineering, electronic engineering, information engineering, Electrical Engineering and Systems Science - Signal Processing, Mathematics - Optimization and Control, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Estimation theory, 020206 networking & telecommunications, Inversion (meteorology), Inverse problem, Nonlinear system, Geophysics, Amplitude, Optimization and Control (math.OC), Phase retrieval, Algorithm
Abstract

SUMMARY Extended formulation of full waveform inversion (FWI), called wavefield reconstruction inversion (WRI), offers potential benefits of decreasing the non-linearity of the inverse problem by replacing the explicit inverse of the wave-equation operator of classical FWI (the oscillating Green functions) with a suitably defined data-driven regularized inverse. This regularization relaxes the wave-equation constraint to reconstruct wavefields that match the data, hence mitigating the risk of cycle skipping. The subsurface model parameters are then updated in a direction that reduces these constraint violations. However, in the case of a rough initial model, the phase errors in the reconstructed wavefields may trap the waveform inversion in a local minimum leading to inaccurate subsurface models. In this paper, in order to avoid matching such incorrect phase information during the early WRI iterations, we design a new cost function based upon phase retrieval, namely a process which seeks to reconstruct a signal from the amplitude of linear measurements. This new formulation, called wavefield inversion with phase retrieval (WIPR), further improves the robustness of the parameter estimation subproblem by a suitable phase correction. We implement the resulting WIPR problem with an alternating-direction approach, which combines the majorization-minimization (MM) algorithm to linearise the phase-retrieval term and a variable splitting technique based upon the alternating direction method of multipliers (ADMM). This new workflow equipped with Tikhonov-Total variation (TT) regularization, which is the combination of second-order Tikhonov and total variation regularizations and bound constraints, successfully reconstructs the 2004 BP salt model from a sparse fixed-spread acquisition using a 3 Hz starting frequency and a homogeneous initial velocity model.

Published
2020
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129. Effect of Surface Treatment of Halloysite Nanotubes (HNTs) on the Kinetics of Epoxy Resin Cure with Amines

Author

Maryam Jouyandeh, Hossein Abdollahi, Henri Vahabi, Mohammad Reza Ganjali, Seyed Mohammad Reza Paran, Vahideh Akbari, Amin Esmaeili, Ahmad Mohaddespour, Sajjad Habibzadeh, Krzysztof Formela, Mohammad Reza Saeb, Zahed Ahmadi, Institute for Color Science and Technology, College of Science of the University of Tehran (UT College of Science), University of Tehran, Tehran University of Medical Sciences (TUMS), Urmia University, Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Amirkabir University of Technology (AUT), University of Gdańsk (UG), School of Engineering Technology and Industrial Trades, and American University of The Middle East [Eqaila]

Subjects
Materials science, Polymers and Plastics, Kinetics, 02 engineering and technology, Activation energy, halloysite nanotubes, engineering.material, 010402 general chemistry, 01 natural sciences, Halloysite, Article, epoxy, lcsh:QD241-441, chemistry.chemical_compound, Differential scanning calorimetry, lcsh:Organic chemistry, Curing (chemistry), ComputingMilieux_MISCELLANEOUS, Nanocomposite, General Chemistry, Epoxy, [CHIM.MATE]Chemical Sciences/Material chemistry, isoconversional method, 021001 nanoscience & nanotechnology, cure kinetics, Silane, 0104 chemical sciences, 3. Good health, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, Chemical engineering, visual_art, engineering, visual_art.visual_art_medium, 0210 nano-technology
Abstract

The epoxy/clay nanocomposites have been extensively considered over years because of their low cost and excellent performance. Halloysite nanotubes (HNTs) are unique 1D natural nanofillers with a hollow tubular shape and high aspect ratio. To tackle poor dispersion of the pristine halloysite (P-HNT) in the epoxy matrix, alkali surface-treated HNT (A-HNT) and epoxy silane functionalized HNT (F-HNT) were developed and cured with epoxy resin. Nonisothermal differential scanning calorimetry (DSC) analyses were performed on epoxy nanocomposites containing 0.1 wt.% of P-HNT, A-HNT, and F-HNT. Quantitative analysis of the cure kinetics of epoxy/amine system made by isoconversional Kissinger&ndash, Akahira&ndash, Sunose (KAS) and Friedman methods made possible calculation of the activation energy (E&alpha, ) as a function of conversion (&alpha, ). The activation energy gradually increased by increasing &alpha, due to the diffusion-control mechanism. However, the average value of E&alpha, for nanocomposites was lower comparably, suggesting autocatalytic curing mechanism. Detailed assessment revealed that autocatalytic reaction degree, m increased at low heating rate from 0.107 for neat epoxy/amine system to 0.908 and 0.24 for epoxy/P-HNT and epoxy/A-HNT nanocomposites, respectively, whereas epoxy/F-HNT system had m value of 0.072 as a signature of dominance of non-catalytic reactions. At high heating rates, a similar behavior but not that significant was observed due to the accelerated gelation in the system. In fact, by the introduction of nanotubes the mobility of curing moieties decreased resulting in some deviation of experimental cure rate values from the predicted values obtained using KAS and Friedman methods.

Published
2020
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130. The hydrogeochemistry of shallow groundwater from Lut Desert, Iran: The hottest place on Earth

Author

Zeinab Matinzadeh, Sara Palacio, Marjan Mashkour, Christopher B. Gardner, W. Berry Lyons, Hossein Akhani, Amir AghaKouchak, Susan A. Welch, Arash Sharifi, Morteza Djamali, ARM, Halophytes and C4 Plants Research Laboratory, Department of Plant Sciences, School of Biology, College of Science, University of Tehran, Department of Civil and Environmental Engineering, Department of Earth System Science, University of California, Archéozoologie, archéobotanique : sociétés, pratiques et environnements (AASPE), Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN), University of Tehran, Faculty of Environment, Enghelab avenue Ghosd street, Tehran, Iran, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Instituto Pirenaico de Ecología (IPE-CSIC), GL2015-71360-P(Ministerio de Economía, Industria y Competitividad, Spain) to SP, andproject i-COOPB20231 (Consejo Superior de InvestigacionesCientíficas, Spain) to SP and ZM. SP was funded by Ramón y Cajalcontract (RYC-2013-14164, Ministerio de Ciencia, Innovación yUniversidades, Spain), Department of Civil and Environmental Engineering [Irvine], University of California [Irvine] (UC Irvine), University of California (UC)-University of California (UC), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Instituto Pirenaico de Ecologìa = Pyrenean Institute of Ecology [Zaragoza] (IPE - CSIC), University of California [Irvine] (UCI), University of California-University of California, Instituto Pirenaico de Ecologia (IPE), and Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)

Subjects
0106 biological sciences, Gypsum, Denitrification, 010504 meteorology & atmospheric sciences, Ecology, Evaporite, Geochemistry, Weathering, engineering.material, 010603 evolutionary biology, 01 natural sciences, 6. Clean water, 13. Climate action, Soil water, [SDE]Environmental Sciences, engineering, Seawater, Dissolution, Ecology, Evolution, Behavior and Systematics, Groundwater, 0105 earth and related environmental sciences, Earth-Surface Processes
Abstract

International audience; This paper presents the first shallow groundwater geochemical data from the Lut Desert (Dasht-e-Lut), one of the hottest places on the planet. The waters are Na-Cl brines that have undergone extensive evaporation, but they are unlike seawater derived brines in that the K + is low and the Ca 2+ > Mg 2+ and HCO 3 − > SO 4 2−. In addition to evapo-concentration, the most saline samples indicate that the dissolution of previously deposited salt also acts as a major control on the geochemistry of these waters. High concentrations of gypsum in surface soils along with the water geochemistry indicate the dissolution, precipitation, and reprecipitation of evaporite salts are very important to the overall chemistry of the near surface environment. As demonstrated by the high H 4 SiO 4 concentrations, the weathering of aluminosilicate minerals also contributes to the solutes present. Fixed nitrogen (NO 3 − + NO 2 −) concentrations suggest little to no denitrification is occurring in these waters. The processes controlling the geochemistry of the Lut waters are similar to those in other hyperarid regions of the Earth.

Published
2020
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131. Epoxy/starch-modified nano-zinc oxide transparent nanocomposite coatings: A showcase of superior curing behavior

Author

Mohammad Reza Saeb, Masoud Mozafari, Payam Zarrintaj, Morteza Ganjaee Sari, Reza Khalili, Mahroo Khaleghi, Meisam Shabanian, Henri Vahabi, Bahram Ramezanzadeh, Seyed Mohammad Reza Paran, Christelle Vagner, Institute for Color Science and Technology, Institute of Standards and Industrial Researches of Iran, Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Faculty of Engineering, University of Tehran, Matériaux divisés, interfaces, réactivité, électrochimie (MADIREL), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), University of Tehran, and Materials and Energy Research center

Subjects
Materials science, Starch, General Chemical Engineering, Oxide, Epoxide, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, chemistry.chemical_compound, Materials Chemistry, [CHIM]Chemical Sciences, Fourier transform infrared spectroscopy, Composite material, ComputingMilieux_MISCELLANEOUS, Curing (chemistry), chemistry.chemical_classification, Nanocomposite, Organic Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, Polymer, Epoxy, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Surfaces, Coatings and Films, [CHIM.POLY]Chemical Sciences/Polymers, chemistry, visual_art, visual_art.visual_art_medium, 0210 nano-technology
Abstract

A new class of transparent epoxy-based nanocomposite coatings containing starch-modified nano-zinc oxide (ZnO-St) is presented. ZnO nanoparticles physically decorated with starch carbohydrate polymer increased compatibility with epoxy chains and sterically prevented flocculation of ZnO nanoparticles. Surface characteristics of pristine ZnO and ZnO-St are studied by FTIR spectroscopy corroborating self-assembled starch molecules on ZnO surface until reaching a complete coverage. Curing behaviors of epoxy and transparent nanocomposites containing ZnO and ZnO-St are studied by the aid of nonisothermal calorimetric analyses at four heating rates to compare the curing enthalpies, onset temperatures, peak temperatures, and curing intervals of transparent coatings. The ZnO-St, particularly at low heating rate of 5 °C/min, prolonged curing (corresponding to ΔT increase of ca. 166 for epoxy to 200 °C for Zn-St/epoxy), and increased the amount of heat release (in the same order from 328 to 380 J/g) due to epoxide ring opening by starch hydroxyl groups. Such novel class of epoxy/ZnO-St nanocomposite coatings can be applied as top-coats because of their transparency. Additionally, from an environmental/biological standpoint, one should consider that starch is a carbohydrate polymer and ZnO is antibacterial, which may put more stress on the use of transparent nanocomposite coatings developed in this work.

Published
2018
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