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International audience; In theVespinae, morphological differences of castes are generally well-marked, except for some Vespa species, where it is difficult to distinguish between future queens and workers in autumn-winter colonies. Individual weights have widely been used as a distinguishing factor but recently cuticular hydrocarbon profiles seems to be the definitive tool, although much more expensive and time-consuming. Parameters such as size (mesos-cutum width), wet and dry weight were analysed, throughout several colonies, to differentiate female castes (workers and gynes) in the hornet Vespa velutina in Europe. These parameters were compared to cuticular hydrocarbon profiles. The results showed that in late autumn, but not earlier, populations are divided into two size groups, which, based on their CHC profiles, can be hypothesized to correspond to workers and gynes. This differentiation mirrored a good separation by size that proves to be more accurate than weight (wet and dry). The size limit between workers and gynes is established at a mesoscutum width of 4.5 mm.

The influence of the solvent used in the processing of Li1.2Ni0.2Mn0.6O2 Li-rich electrodes has been thoroughly studied using complementary chemical, structural and electrochemical characterization techniques. Structural characterization has demonstrated that the bulk chemical composition and the structure of the material remain unchanged when processing the electrode in organic and aqueous media. 6Li solid state NMR measurements revealed that no perceptible variations of the signal positions and intensities were observed for the different samples, indicating the absence of H+/Li+ ionic exchange upon water exposition. Full coin-cells with the waterborne and organic processed Li-rich cathodes and graphite anodes delivered exceptional capacity retention during more than 250 cycles at 100% depth of discharge. This study proves that water-based binders can be used both for the anode and the cathode formulations of the next generation of Li-ion batteries.

We present an efficient method for the encapsulation and fixation of octadecylamine coated CdSe/ZnS quantum dots. This is achieved by incorporating the QDs into core-shell particles made of PS/DVB (core)/PMMA/DVB (shell) cross linked polymeric phases synthesized in two stages. The first stage comprises the production of a hybrid PS/DVB core with QD nanoparticles located at the interface of the polymer particle and aqueous phase. In the second stage a PMMA/DVB shell is produced on the hybrid cores, burying the QDs within the composite particle and substantially minimizing the migration of the QDs out of the particles. The stability of the QDs within the core-shell particles is proven by assessing the fluorescence over long periods of time. Contrary to what happens to the core particle dispersion that lost fluorescence in few weeks, the fluorescence emission of the core-shell particles preserves the optical properties of the neat QDs for more than 46 weeks.

Entomopathogenic fungi such as Beauveria spp. have potential applications in the biocontrol of insect pests but little is known regarding their infectivity to the pine weevil Pissodes nemorensis. In this study, five isolates of Beauveria pseudobassiana and five isolates of Beauveria bassiana were tested for characteristics correlating with virulence on P. nemorensis. Isolate UAMH301 had the lowest mean lethal concentration value whereas the highest value was obtained with isolate LRC137. Growth rate was negatively correlated with virulence in B. bassiana, because isolate LRC137, the least virulent isolate, grew much more rapidly than the other B. bassiana isolates on SDYA. In contrast, its growth on a hyperosmotic medium was the slowest. Sporulation rate and conidial area were not correlated with virulence. Mycelial cell density was positively correlated with virulence in both species, and the four tested genes appear to be one-copy genes. Bbchit1 and Bbhog1, genes respectively encoding a chitinase and a protein kinase, induced relative expression levels were positively correlated with virulence in B. pseudobassiana. We discuss in terms of previous morphological, physiological and genetic parameters related to virulence in Beauveria and the importance of testing the expression of putative virulence genes in comparison with their basal transcript levels.

The sodium-vanadium fluorophosphate family has been actively investigated recently, but few examples tackle chemical doping or the substitution of vanadium. This work presents a series of iron-doped compounds Na

Bio-based polymeric nanocomposites (NCs) with enhanced electrical conductivity and rigidity were obtained by adding multi-walled carbon nanotubes (CNTs) to a commercial bio-based polyamide 4,10 (PA410). Two different types of commercial CNTs (Cheap Tubes and Nanocyl NC7000TM) and two different preparation methods (using CNTs in powder form and a PA6-based masterbatch, respectively) were used to obtain melt-mixed PA410/CNT NCs. The effect of the preparation method as well as the degree of dispersion and aspect ratio of the CNTs on the electrical and mechanical properties of the processed NCs was studied. Superior electrical and mechanical behavior was observed in the Nanocyl CNTs-based NCs due to the enhanced dispersion and higher aspect ratio of the nanotubes. A much more significant reduction in aspect ratio was observed in the Cheap Tubes CNTs than in the Nanocyl CNTs. This was attributed to the fact that the shear stress applied during melt processing reduced the length of the CNTs to similar lengths in all cases, which pointed to the diameter of the CNTs as the key factor determing the properties of the NCs. The PA6 in the ternary PA410/PA6/CNT system led to improved Young&rsquo, s modulus values because the reinforcing effect of CNTs was greater in PA6 than in PA410.

21st century engineers have to confront global society’s competitiveness, so technical and technological competences have to be enriched with critical thinking, problem solving, collaboration, communication and creativity skills. To this end, teaching methodologies like Project-Based Learning (PBL) together with cooperative work, to cover the educational needs of future engineering graduates, should be promoted in class. This paper presents the SimABP project, an action where we simulate a work experience in the CAD subject presenting a real challenge to the students, tightly linking academy to real labour reality. In addition, we also define specific rubrics for evaluating the competences and we show the most significant results obtained. Our action has increased the satisfaction and motivation of the students, and the marks obtained in technical skills have been higher.

Which didactic methodology is the most appropriate considering the contents of my subject? What are the activities that suit my possibilities? What evaluation method is fair and formative for the competences of my subject? The teaching team of the subject of Graphic Expression in the Engineering of the Engineering School of Bilbao (UPV/EHU) decided to act in order to improve the teaching-learning process. For this purpose a restructuring of the entire subject that would be carried out by making a disruptive approach to redesign the subjetc was thought. The main objective was to capture the students’ interest in the subject and, as a result, improve the success rate. For this purpose, a restructuring of the whole subject was sought by applying educational methodologies and updated technologies according to the new requirements by the students and the teachers. The main idea is to give importance to the knowledge and ability of extracting the necessary data to represent graphically the reality, identifying the real problem posed with a method of theoretical resolution. At the same time, to minimize the importance of memorizing steps, data can be consulted in the bibliography. With the objective of implementing the main ideas above, the teaching team inquired about pedagogic models, and found that the Flipped Classroom suited the necessary characteristics, mainly the effective use of time in the classroom. Finally, it is important to notice that the creative process followed has allowed the teaching team to unify criteria and agree on results. This way, all members have felt involved in the project.

This work applies statistical analysis, and classical and advanced machine learning algorithms to classify 7714 aggregates into four categories according to their shape. The aggregates under study are obtained from several grades of carbon black: Vulcan XC 605, Vulcan XC 72, CSX 691, Printex 25, N990, and N762. The classification of the shape is of great significance in order to explain and predict the end-use properties of the composite materials, like mechanical properties. The proposed approach combines transmission electron microscopy and automated image analysis to obtain the dataset of the morphological features that defines the shape of the aggregate, and statistical analysis and machine learning techniques to create the classification models using feature transformation and reduction, parameter tuning, and validation methods in order to achieve robust classification models. The best result is obtained from a classification tree based on evolutionary algorithms with a principal component analysis-based feature reduction that reports an acceptable accuracy, thereby validating both the final chosen model and the methodology.

The present work describes a methodology to implement microstructural data obtained from TEM tomography into finite element (FE) simulation software. In this first approach the tomographic reconstruction is treated with different software to create a 3D realistic model of the microstructure of the composite. This realistic model is compared against 2D image-based models via FE simulations in order to compare the mechanical behavior achieved with both procedures. After this first study the results obtained with both types of model are similar. These results are a promising starting point for the development of this novel methodology for obtaining nanocomposite FE models from TEM tomography with realistic results.

Soil moisture is an important factor in soil systems. To examine the effects of a progressive loss of moisture (gradual drought) on the soil oribatid community of two ecosystems (pedunculate oak and holm oak forests), a laboratory experiment was carried out to (1) record changes in abundance, diversity and species composition and (2) determine drought-resistant and drought-sensitive species. In both ecosystems, the maximum values for species abundance were at the beginning of the experiment; by the end of the experiment, only a few species remained. The species that disappeared first were Damaeus onustus, Microppia minus, Suctobelba regia, Suctobelba trigona, Liochthonius brevis, Quadroppia pseudocircumita, Rhinoppia obsoleta and Suctobelbella subcornigera. Those that survived until the end of the experiment were Hermanniella dolosa, Odontocepheus elongatus and Tectocepheus velatus. The progressive rate of water loss (drought) was similar in both experiments. Species richness decreased in drier co...

Improvement of life-time is an important issue in the development of Li-ion batteries. Aging mechanisms limiting the life-time can efficiently be characterized by physico-chemical analysis of aged cells with a variety of complementary methods. This study reviews the state-of-the-art literature on Post-Mortem analysis of Li-ion cells, including disassembly methodology as well as physico-chemical characterization methods for battery materials. A detailed scheme for Post-Mortem analysis is deduced from literature, including pre-inspection, conditions and safe environment for disassembly of cells, as well as separation and post-processing of components. Special attention is paid to the characterization of aged materials including anodes, cathodes, separators, and electrolyte. More specifically, microscopy, chemical methods sensitive to electrode surfaces or to electrode bulk, and electrolyte analysis are reviewed in detail. The techniques are complemented by electrochemical measurements using reconstruction methods for electrodes built into half and full cells with reference electrode. The changes happening to the materials during aging as well as abilities of the reviewed analysis methods to observe them are critically discussed.

This work compares several automatic classification methods with visual expert decision classification. The classification is based on carbon black aggregates into one of the four morphological classes that were proposed by Herd. The automatic methodologies were performed in several steps: transmission electron microscopy image processing to compute a set of twenty-one morphological characteristics, multivariate analysis of the dataset to avoid the curse of dimensionality in classification problems, and built, test and validate machine-learning techniques to classify the aggregates. In the other hand six expert researchers made a visual classification of the aggregates and later, a statistical analysis was conducted to classify the aggregates according to some defined weights. And finally, a comparison of the methods decided which method obtained the highest accuracy and was the most reliable between the compared ones.

Resumen basado en el de los autores Universidad del País Vasco. Escuela Técnica Superior de Ingeniería (Bilbao) La universidad está en proceso de aplicación de nuevas metodologías educativas. Las consecuencias más relevantes son el aumento considerable de trabajo para el profesorado y que el alumnado pasa a ser parte activa del proceso, siendo protagonista de su propio aprendizaje. El proceso no parece ser tan inmediato como un mero cambio de metodologías, y los resultados pueden tardar en llegar en función del acierto en las innovaciones. A ello se une el hecho de que gran parte del éxito depende de la actitud del alumnado, que debe asumir el rol de persona independiente y responsable de su propia formación. Se muestran los resultados de encuestas realizadas para intentar conocer la motivación y las preferencias sobre la metodología docente, su opinión sobre las dificultades y expectativas que tienen respecto de la asignatura. Todo ello con el reto de motivar al alumnado de primer curso. Entre las conclusiones más llamativas, un elevado porcentaje de estudiantes tiene formación previa de la asignatura, sin embargo, pocos consideran llegar bien preparados. También que eran preferibles los métodos clásicos, es decir, que el profesorado explique y haga ejemplos en clase y que la documentación esté disponible en papel. ESP

While manufacturing composite materials, reinforcement fillers inevitable collide with each other and subsequently they congregate to aggregates with different shapes. The shape of these nanoparticles aggregates are of great significance for the mechanical material properties and in consequence, knowing the percentage of aggregates of each shape within of a specific group of shapes can give an idea of the final properties of the material. This work classifies aggregates, a new dataset of 5713 carbon black aggregates gathered based on transmission electron microscopy image processing, using several classification trees and rule-based methods. Based on these methods several models are built, trained and tested to perform the classification. And then, the most reliable and accurate model to classify aggregates is selected, obtaining a testing accuracy of the 74.57% according to their shape.

Nowadays, the electric vehicle is one of the most promising alternatives for sustainable transportation. However, the battery, which is one of the most important components, is the main contributor to environmental impact and faces recycling issues. In order to reduce the carbon footprint and to minimize the overall recycling processes, this paper introduces the concept of re-use of electric vehicle batteries, analyzing some possible second-life applications. Methods First, the boundaries of the life cycle assessment of an electric vehicle are defined, considering the use of the battery in a second-life application. To perform the study, we present eight different scenarios for the second-life application. For each case, the energy, the efficiency, and the lifetime of the battery are calculated. Additionally, and based on the global warming potential, the environmental impact of the electric vehicle and its battery on a second-life application is determined for each scenario. Finally, an environmentally focused discussion on battery electrodes and research trends is presented. Results and discussion For the selected scenarios, the second life of the battery varies from 8 to 20 years depending on the application and the requirements. It has been observed that the batteries connected to the electricity grid for energy arbitrage storage have the highest impact per provided kilowatt hour. On the contrary, the environmental benefit comes from applications working with renewable energy sources and presenting a longer lifetime. We pointed out that a correlation between cycling conditions and degradation mechanisms of the electrode materials is compulsory for proper use of the electric vehicle battery in a second-life application. Conclusions To limit the environmental impact, batteries should be associated with renewable energy sources in stationary applications. However, it is more profitable to re-use Li-ion batteries than to use new lead-acid batteries. Although many batteries applied for electric vehicles use graphite-based anodes, the latter may not be the most suitable for the second-life application. A better understanding of Li-ion battery degradation during the second-life application is required for the different existing chemistries.

The degree of trophic plasticity in soil animals is intensely debated. We used stable isotope ratios (15N/14N, 13C/12C) of oribatid mite species from six oak (Quercus robur) forests to investigate (1) if trophic niches vary between forests and (2) the range of trophic levels spanned by oribatid mites. Using litter as baseline stable isotope signatures of most oribatid mite species differed between forests. Therefore, the stable isotope signatures were re-calibrated using stable isotope values of Platynothrus peltifer as primary decomposer species occurring in each of the six forests. Re-calibrated values of nine species (Cerachipteria jugata, Damaeus clavipes, Neotrichoppia variabilis, Oppia denticulata, Hermaniella dolosa, Steganacarus magnus, Ceratozetes peritus, Nanhermannia nana, Xenillus tegeocranus, Eremaeus cordiformis) differed significantly between forests indicating trophic plasticity in most of the studied oribatid mite species. Overall, calibrated stable isotope ratios spanned over 8.7 δ units for 15N and 5.9 δ units for 13C indicating that in forest ecosystems oribatid mite species span about three trophic levels.

The yellow-legged hornet Vespa velutina nigrithorax du Buysson (Hymenoptera: Vespidae) is an Asian native species which has now established in parts of Europe. Since its detection in France in 2005 it has spread quickly across the country and also spread to the Iberian Peninsula. This paper compiles the most recent data about its spread and distribution on the Spanish mainland. The efficacy of using Veto-Pharma© traps as a control method is also discussed. Dissemination du frelon asiatique Vespa velutina nigrithorax du Buysson (Hymenoptera: Vespidae) dans le nord de l'Espagne Le frelon asiatique Vespa velutina nigrithorax du Buysson (Hymenoptera: Vespidae) est une espece native d'Asie qui est maintenant etablie dans certaines parties de l'Europe. Depuis sa detection en France en 2005, il s'est dissemine rapidement dans tous le pays et s'est aussi dissemine a la peninsule iberique. Cet article presente les donnees les plus recentes sur sa dissemination et sa repartition en Espagne. L'efficacite du piege Veto-pharma© comme methode de lutte est egalement discutee. Pacпpocтpaнeниe жeлтoнoгoгo шepшня Vespa velutina nigrithorax Buysson (Hymenoptera: Vespidae) пo ceвepнoй Иcпaнии Жeлтoнoгий шepшeнь Vespa velutina nigrithorax Buysson (Hymenoptera: Vespidae) являeтcя видoм aзиaтcкoгo пpoиcxoждeния, кoтopый в нacтoящee вpeмя aкклимaтизиpoвaлcя в нeкoтopыx чacтяx Eвpoпы. C мoмeнтa eгo выявлeния вo Фpaнции в 2005 г. oн быcтpo pacпpocтpaнилcя пo вceй cтpaнe, a тaкжe нa Пиpeнeйcкoм пoлyocтpoвe. B cтaтьe пpивoдятcя пocлeдниe дaнныe o eгo pacпpocтpaнeнии и pacпpocтpaнeннocти в мaтepикoвoй Иcпaнии. Paccмaтpивaeтcя тaкжe вoпpoc эффeктивнocти иcпoльзoвaния лoвyшeк Veto-Pharma trap© в кaчecтвe cпocoбa бopьбы c ним.

A wide range of mechanical properties of carbon-black reinforced rubber blends are usually studied to evaluate their performance according to the initial material composition. Different amount of each composition element generate rubber blends with different mechanical properties, subsequently model the relationship between composition and mechanical properties could contribute useful information and could also save manufacturer industries significant amounts of capital. This study models tensile strength property using linear regression techniques and low errors were obtained in comparison with the values obtained from real experiments. Linear regression and generalized linear regression techniques, simple and enhanced with Gradient Boosting techniques, were used to create linear models with RMSE errors of approximately 25.33% in tensile strength prediction.

Litio-ioizko baterien hedapena etengabea izan da azken urteetan gizartearen energia beharrizanak asetzeko. Modu orokor batean litio-ioizko deitzen zaien baterien artean hainbat sistema ezberdindu daitezke, osatzen duten material aktiboen eta ondorioz, gertatzen diren erreakzio elektrokimikoen arabera. Konposizio kimikoa ez da ordea baterien funtzionamendua definitzen duen aldagai bakarra. Bateriaren fabrikazio prozesuan finkatzen diren beste hainbat parametrok ere, hala nola, elektrodoen porositateak, anodo eta katodoaren arteko masa erlazioak, elektrolito bolumenak..., eragin zuzena dute baterien propietateetan. Artikulu honetan «pouch cell» motako baterien fabrikazio prozesua deskribatuko da, parametro hauen garrantzia azalduz.

Nanoparticulate NiO and NiO/C composites with different carbon proportions have been prepared for anode application in lithium and sodium ion batteries. Structural characterization demonstrated the presence of metallic Ni in the composites. Morphological study revealed that the NiO and Ni nanoparticles were well dispersed in the matrix of amorphous carbon. The electrochemical study showed that the lithium ion batteries (LIBs), containing composites with carbon, have promising electrochemical performances, delivering specific discharge capacities of 550 mAh/g after operating for 100 cycles at 1C. These excellent results could be explained by the homogeneity of particle size and structure, as well as the uniform distribution of NiO/Ni nanoparticles in the in situ generated amorphous carbon matrix. On the other hand, the sodium ion battery (NIB) with the NiO/C composite revealed a poor cycling stability. Post-mortem analyses revealed that this fact could be ascribed to the absence of a stable Solid Electrolyte Interface (SEI) or passivation layer upon cycling.

Concentrations of four monoterpenes were determined in needles of Pinus radiata (D.Don) (Pinales: Pinaceae) trees that were attacked or nonattacked by Tomicus piniperda (L.) (Coleoptera: Scolytinae). Compounds were identified and quantified by gas chromatography–mass spectrometry. The mean ambient temperature was obtained using climate-recording data loggers. The effect of limonene on field aggregation was also evaluated at three limonene release rates using Lindgren attractant-baited traps and trap logs. Attacked trees produced less α-pinene in March, July, and November than nonattacked trees, less β-pinene in July and November, and less limonene from May to November. Limonene reduced the attraction of T. piniperda to attractant-baited traps and trap logs. Results were linked to better responses to high temperatures, with respect to terpene contents, by the nonattacked trees after the spring attack.

The evolution of the morphology of an acrylic/CeO2 hybrid latex synthesized by a two step seeded semibatch emulsion polymerization process was investigated. The seed was produced by batch miniemulsion polymerization and in the second step a neat monomer preemulsion was fed to the seed to increase the solids content and encapsulate the inorganic material. The morphology of the hybrid miniemulsion droplets, the seed and the final latex was analyzed by TEM. The morphologies achieved could be explained by theoretical equilibrium morphology maps based on the interfacial tensions of the monomeric, polymeric, inorganic and aqueous phases. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 792–799

Mastering the relationship between the final mechanical properties of carbon black reinforced rubber blends and their composition is a key advantage for an efficient design of the composition of the blend. In this work, some models to predict three relevant physical attributes of rubber blends — modulus at 100% deformation, Shore A hardness, and tensile strength — are built by machine learning methods and subsequently evaluated. Linear regression, artificial neural networks, support vector machine, and regression trees are used to generate the models. The number of used samples and the values for the input variables is determined by a Taguchi design of experiments, and prior to the modeling the uncertainty of the experimental data was analyzed.

An original method is presented to classify nano-particle aggregates into one of the morphological classes that were previously proposed in the literature. Carbon black was selected as a study case in this work, since it is a nanoreinforcement used massively in many industries, but the proposed method can be applied to other particulate aggregates as well. This methodology consists of three steps: (i) transmission electron microscopy image processing to compute a set of twenty-one morphological characteristics for each aggregate including the new attributes proposed herein, (ii) a multivariate analysis of the dataset to reduce the problem dimensionality and (iii) creation and assessment of decision trees based on evolutionary algorithms to classify the aggregates. The effectiveness of the method was proven for a balanced-per-class sample of forty-eight selected aggregates. The original dimension of the problem is reduced to three principal components, which explain 90% of the total variance. The best model classifies an aggregate into one of the four morphological classes in a simple comparison process. The accuracy of the applied model to classify new aggregates was 75%.

The efficacy of 23 compounds in repelling Culicoides biting midges (Diptera: Ceratopogonidae), particularly Culicoides obsoletus (Meigen) females, was determined by means of a Y-tube olfactometer. The 10 most effective compounds were further evaluated in landing bioassays. The six most promising compounds (including chemical and plant-derived repellents) were evaluated at 10% and 25% concentrations in field assays using Centers for Disease Control (CDC) light traps. At least three compounds showed promising results against Culicoides biting midges with the methodologies used. Whereas olfactometer assays indicated DEET at 1 µg/µL to be the most effective repellent, filter paper landing bioassays showed plant-derived oils to be better. Light traps fitted with polyester mesh impregnated with a mixture of octanoic, decanoic and nonanoic fatty acids at 10% and 25% concentrations collected 2.2 and 3.6 times fewer midges than control traps and were as effective as DEET, which is presently considered the reference standard insect repellent. The best plant-derived product was lemon eucalyptus oil. Although these have been reported as safe potential repellents, the present results indicate DEET and the mixture of organic fatty acids to be superior and longer lasting.