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2. Distilling a Materials Synthesis Ontology

Author

Kim, E, Huang, K, Kononova, O, Ceder, G, and Olivetti, E

Abstract

Methods sections adopt a common practice of past-tense narrative using passive voice. Here, we discuss issues with current and historical writing conventions in materials science literature and propose a structured way to facilitate reproducibility, clarity, and machine readability.

Published
2019

4. Heterogeneous nucleation and heat flux avalanches in La(Fe,Si)$_{13}$ magnetocaloric compounds near the critical point

Author

Bennati, C., Gozzelino, L., Olivetti, E. S., and Basso, V.

Subjects
Condensed Matter - Materials Science
Abstract

The phase transformation kinetics of LaFe$_{11.41}$Mn$_{0.30}$Si$_{1.29}$-H$_{1.65}$ magnetocaloric compound is addressed by low rate calorimetry experiments. Scans at 1 mK/s show that its first order phase transitions are made by multiple heat fllux avalanches. Getting very close to the critical point, the step-like discontinuous behavior associated with avalanches is smoothed out and thermal hysteresis disappears. This result is confirmed by magneto-resistivity measurements and allows to measure accurate values of the zero field hysteresis ($\Delta T_{hyst}$ = 0.37 K) and of the critical field (H$_c$ = 1.19 T). The number and magnitude of heat flux avalanches change with magnetic field, showing the interplay between the intrinsic energy barrier between phases and the microstructural disorder of the sample., Comment: 5 pages, 4 figures

Published
2016
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5. Materials Synthesis Insights from Scientific Literature via Text Extraction and Machine Learning

Author

Kim, E, Huang, K, Saunders, A, McCallum, A, Ceder, G, and Olivetti, E

Subjects
Materials, Chemical Sciences, Engineering
Abstract

In the past several years, Materials Genome Initiative (MGI) efforts have produced myriad examples of computationally designed materials in the fields of energy storage, catalysis, thermoelectrics, and hydrogen storage as well as large data resources that are used to screen for potentially transformative compounds. The bottleneck in high-Throughput materials design has thus shifted to materials synthesis, which motivates our development of a methodology to automatically compile materials synthesis parameters across tens of thousands of scholarly publications using natural language processing techniques. To demonstrate our framework's capabilities, we examine the synthesis conditions for various metal oxides across more than 12 thousand manuscripts. We then apply machine learning methods to predict the critical parameters needed to synthesize titania nanotubes via hydrothermal methods and verify this result against known mechanisms. Finally, we demonstrate the capacity for transfer learning by using machine learning models to predict synthesis outcomes on materials systems not included in the training set and thereby outperform heuristic strategies.

Published
2017

6. Le controversie arbitrabili

Author

Olivetti E., Ansaldi L., Bossi A., Locatelli F., Oglio L., Paccoia M., Silvestri E., Vanoni S., Vanoni, Silvia, Silvia Vanoni (ORCID:0000-0001-5371-1023), Olivetti E., Ansaldi L., Bossi A., Locatelli F., Oglio L., Paccoia M., Silvestri E., Vanoni S., Vanoni, Silvia, and Silvia Vanoni (ORCID:0000-0001-5371-1023)

Abstract

Il contributo è parte di un capitolo in tema di disciplina dell’arbitrato nelle controversie societarie, inserito in un più ampio volume che si occupa delle (poche) modifiche della disciplina dell’arbitrato introdotte dal d.lgs. 149/2022 (c.d. “riforma Cartabia”) e dei possibili profili evolutivi di tale strumento di definizione delle controversie alternativo al giudizio ordinario. Lo scritto riprende e si concentra sul tema dell’ambito di applicazione dell’arbitrato in materia societaria, con particolare riferimento alle dispute che insorgono nelle s.p.a. e s.r.l. L’Autrice constata che la riforma Cartabia è stata una “occasione mancata” di fare chiarezza sulla possibilità di definire tramite procedura arbitrale alcune tipologie di dispute societarie, essendo stato risolto solo il dubbio relativo al trattamento delle società semplici. Dopo un esame degli orientamenti sviluppati dalla giurisprudenza e dalla dottrina nell’applicazione della disciplina speciale dell’arbitrato societario introdotta con il d.lgs. 5/2003, l’A. conclude per l’ammissibilità di una interpretazione estensiva della nozione di controversie arbitrabili nel contesto in esame e formula alcune proposte de iure condendo a favore della compromettibilità anche delle liti che insorgono nell’ambito di società che fanno ricorso al mercato del capitale di rischio.

Published
2024

7. Influence of sample geometry on inductive damping measurement methods

Author

Liebing, N., Serrano-Guisan, S., Caprile, A., Olivetti, E. S., Celegato, F., Pasquale, M., Müller, A., and Schumacher, H. W.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

We study the precession frequency and effective damping of patterned permalloy thin films of different geometry using integrated inductive test structures. The test structures consist of coplanar wave guides fabricated onto patterned permalloy stripes of different geometry. The width, length and position of the permalloy stripe with respect to the center conductor of the wave guide are varied. The precession frequency and effective damping of the different devices is derived by inductive measurements in time and frequency domain in in-plane magnetic fields. While the precession frequencies do not reveal a significant dependence on the sample geometry we find a decrease of the measured damping with increasing width of the permalloy centered underneath the center conductor of the coplanar wave guide. We attribute this effect to an additional damping contribution due to inhomogeneous line broadening at the edges of the permalloy stripes which does not contribute to the inductive signal provided the permalloy stripe is wider than the center conductor. Consequences for inductive determination of the effective damping using such integrated reference samples are discussed.

Published
2013
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9. Disordered to ordered phase transformation: Correlation between microstructure and magnetic properties in Fe–Pd thin films.

Author

Bahamida, S., Fnidiki, A., Coïsson, M., Olivetti, E. S., Barrera, G., Celegato, F., Tiberto, P., and Boudissa, M.

Subjects
PHASE transitions, MAGNETIC properties, MAGNETIC measurements, MICROSTRUCTURE, SILICON films, THIN films, MAGNETIC alloys
Abstract

The kinetics of the transformation from the disordered to the ordered phase has been studied in Fe56Pd44 thin films deposited on silicon substrates by Joule evaporation. Subsequent thermal treatments at 550 °C in vacuum were performed at different annealing times to promote the formation and the optimization of the ordered L10 FePd phase. X-ray diffraction allowed us to investigate the microstructure of the samples (grain size, volume fraction of the transformed phase, order parameter of the ordered phase, and average order of the alloy), whereas magnetic measurements allowed us to evaluate coercivity and to independently estimate the volume fraction of the ordered L10 phase. The kinetics of the transformation turned out to reach completion after 20 min of annealing time with the grain size growing with a power law with an exponent equal to 8.24. The resulting monophasic film has a high density of defects, which contribute to the magnetic coercivity. A linear relationship between the coercive field and the average order parameter of the alloy has been established. Finally, the evolution of the transformed phase obeys Avrami's law with an exponent of ∼0.4, indicating that the transformation is controlled by the nucleation mechanism without grain growth. [ABSTRACT FROM AUTHOR]

Published
2022
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10. Passaggio alla psicoterapia online durante la pandemia da Coronavirus (Covid-19): variabili associate alla soddisfazione dei pazienti. Il caso del Centro Medico Santagostino

Author

Staccini, L, Cavadini, D, Gravagnuolo, R, Olivetti, E, Bongiovanni, C, Calati, R, Madeddu, F, Mandelli, L, Porcelli, S, Laura Staccini, Daniele Cavadini, Rosa Gravagnuolo, Elena Olivetti, Camilla Bongiovanni, Raffaella Calati, Fabio Madeddu, Laura Mandelli, Stefano Porcelli, Staccini, L, Cavadini, D, Gravagnuolo, R, Olivetti, E, Bongiovanni, C, Calati, R, Madeddu, F, Mandelli, L, Porcelli, S, Laura Staccini, Daniele Cavadini, Rosa Gravagnuolo, Elena Olivetti, Camilla Bongiovanni, Raffaella Calati, Fabio Madeddu, Laura Mandelli, and Stefano Porcelli

Abstract

La pandemia da Coronavirus (Covid-19) ha richiesto l’adattamento di pazienti e psicoterapeuti a un’evoluzione del tradizionale setting “in presenza” alla videoterapia (VT). La VT ha visto una progressiva diffusione prima come passaggio obbligato e, poi, come nuova modalità alternativa o integrabile. L’obiettivo di questo lavoro è indagare il grado di soddisfazione dei pazienti nel passaggio alla VT, unitamente all’impatto di attitudini/esperienze pregresse e attuali riguardo alla VT stessa. A tal fine, è stato sviluppato un questionario ad hoc, inviato via e-mail a tutti i pazienti seguiti in psicoterapia, tra marzo e giugno 2020, presso il servizio di Psicologia,Psicoterapia e Psichiatria del Centro Medico Santagostino. È stata condotta un’analisi della distribuzione delle risposte nel campione (n = 111) e un modello di regressione multipla per valutare l’effetto di specifiche variabili sul grado di soddisfazione espresso dai pazienti. Le difficoltà nell’uso dei sistemi di video-comunicazione e di postazione predicono una minore soddisfazione per la VT. Nell’esperienza di VT, un senso di maggiore spontaneità con il terapeuta e la percezione di impatto sul modo di comunicare correlano, rispettivamente positivamente enegativamente, con la soddisfazione per la VT. Al fine di una migliore esperienza di VT, proponiamo di considerare diverse variabili contestuali e specifiche che ne caratterizzano il setting.

Published
2023

15. SciPy 1.0: fundamental algorithms for scientific computing in Python: 24 February 2020 : An amendment to this paper has been published and can be accessed via a link at the top of the paper

Author

Virtanen, P., Gommers, R., Oliphant, T.E., Haberland, M., Reddy, T., Cournapeau, D., Burovski, E., Peterson, P., Weckesser, W., Bright, J., Walt, S.J., Brett, M., Wilson, J., Millman, K.J., Mayorov, N., Nelson, A.R.J., Jones, E., Kern, R., Larson, E., Carey, C.J., Polat, I., Feng, Y., Moore, E.W., VanderPlas, J., Laxalde, D., Perktold, J., Cimrman, R., Henriksen, I., Quintero, E.A., Harris, C.R., Archibald, A.M., Ribeiro, A.H., Pedregosa, F., Mulbregt, P., Vijaykumar, A., Bardelli, A.P., Rothberg, A., Hilboll, A., Kloeckner, A., Scopatz, A., Lee, A., Rokem, A., Woods, C.N., Fulton, C., Masson, C., Häggström, C., Fitzgerald, C., Nicholson, D.A., Hagen, D.R., Pasechnik, D.V., Olivetti, E., Martin, E., Wieser, E., Lenders, F., Silva, Fabrice, Wilhelm, F., Young, G., Price, G.A., Ingold, G.-L., Allen, G.E., Lee, G.R., Audren, H., Probst, Irvin, Dietrich, J.P., Silterra, J., Webber, J.T., Slavič, J., Nothman, J., Buchner, J., Kulick, J., Schönberger, J.L., Miranda Cardoso, J.V., Reimer, J., Harrington, J., Rodríguez, J.L.C., Nunez-Iglesias, J., Kuczynski, J., Tritz, K., Thoma, M., Newville, M., Kümmerer, M., Bolingbroke, M., Tartre, M., Pak, M., Smith, N.J., Nowaczyk, N., Shebanov, N., Pavlyk, O., Brodtkorb, P.A., Lee, P., McGibbon, R.T., Feldbauer, R., Lewis, S., Tygier, S., Sievert, S., Vigna, S., Peterson, S., More, S., Pudlik, T., Oshima, T., Pingel, T.J., Robitaille, T.P., Spura, T., Jones, T.R., Cera, T., Leslie, T., Zito, T., Krauss, T., Upadhyay, U., Halchenko, Y.O., Vázquez-Baeza, Y., SciPy 1.0, Contributors, Low Temperature Laboratory, TKK Helsinki University of Technology (TKK), Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Tribologie et Dynamique des Systèmes (LTDS), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-École Nationale des Travaux Publics de l'État (ENTPE)-Ecole Nationale d'Ingénieurs de Saint Etienne-Centre National de la Recherche Scientifique (CNRS), SNECMA Villaroche [Moissy-Cramayel], Safran Group, New Technologies Research Centre [Plzeň] (NTC), University of West Bohemia [Plzeň ], Institute of Environmental Physics [Bremen] (IUP), University of Bremen, Istituto Nazionale di Ricerca Metrologica (INRiM), Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Laboratoire de Mécanique et d'Acoustique [Marseille] (LMA ), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Sons, Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), European Synchrotron Radiation Facility (ESRF), Lab-STICC_ENSTAB_CID_PRASYS, Laboratoire des sciences et techniques de l'information, de la communication et de la connaissance (Lab-STICC), École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT), Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, University of Chicago, Consortium of Advanced Radiation Sciences, Advanced Photon Source, GSECARS, University of Chicago, Laboratoire de physique des gaz et des plasmas (LPGP), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), The Open University [Milton Keynes] (OU), Nobeyama Radio Observatory, Gommers, Ralf [0000-0002-0300-3333], Haberland, Matt [0000-0003-4806-3601], Reddy, Tyler [0000-0003-2364-6157], van der Walt, Stéfan J. [0000-0001-9276-1891], Millman, K. Jarrod [0000-0002-5263-5070], Nelson, Andrew R. J. [0000-0002-4548-3558], Laxalde, Denis [0000-0002-5540-4825], Ribeiro, Antônio H. [0000-0003-3632-8529], van Mulbregt, Paul [0000-0002-2382-8308], Apollo - University of Cambridge Repository, van der Walt, Stéfan J [0000-0001-9276-1891], Millman, K Jarrod [0000-0002-5263-5070], Nelson, Andrew RJ [0000-0002-4548-3558], Ribeiro, Antônio H [0000-0003-3632-8529], Quansight LLC, California Polytechnic State University [San Luis Obispo] (CAL POLY), Los Alamos National Laboratory (LANL), AUTRES, National Research University Higher School of Economics [St. Petersburg], Tallinn Technical University, University of California [Berkeley] (UC Berkeley), University of California (UC), University of Birmingham [Birmingham], Skolkovo Innovation Center, Australian Nuclear Science and Technology Organisation [Australie] (ANSTO), Enthought Inc, University of Washington [Seattle], University of Massachusetts [Amherst] (UMass Amherst), University of Massachusetts System (UMASS), Bruker BioSpin Corporation, Université de Lyon-Université de Lyon-École Nationale des Travaux Publics de l'État (ENTPE)-Ecole Nationale d'Ingénieurs de Saint Etienne (ENISE)-Centre National de la Recherche Scientifique (CNRS), University of Texas at Austin [Austin], Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Universidade Federal de Minas Gerais [Belo Horizonte] (UFMG), Google LLC, Laboratoire Chrono-environnement (UMR 6249) (LCE), École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique (IMT Atlantique), and Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS)

Subjects
FOS: Computer and information sciences, Computer science, 01 natural sciences, Biochemistry, Computer Science - Software Engineering, 631/45/56, Data Structures and Algorithms (cs.DS), 010303 astronomy & astrophysics, computer.programming_language, 0303 health sciences, Signal processing, Signal Processing, Computer-Assisted, Computational Physics (physics.comp-ph), ddc, Linear algebra, Perspective, Minification, Physics - Computational Physics, Algorithm, Algorithms, Biotechnology, De facto standard, FOS: Physical sciences, Image processing, History, 21st Century, Models, Biological, 706/703/559, Python (Computer program language), Computational science, 03 medical and health sciences, Computer Science - Data Structures and Algorithms, 0103 physical sciences, Computer Simulation, [INFO]Computer Science [cs], ddc:530, Cluster analysis, Molecular Biology, Scientific computing, 030304 developmental biology, Sparse matrix, software, Computational Biology, Cell Biology, Python (programming language), History, 20th Century, [INFO.INFO-NA]Computer Science [cs]/Numerical Analysis [cs.NA], Software Engineering (cs.SE), Nonlinear Dynamics, Linear Models, Computer Science - Mathematical Software, Programming Languages, 631/114, computer, Mathematical Software (cs.MS), Python
Abstract

SciPy is an open source scientific computing library for the Python programming language. SciPy 1.0 was released in late 2017, about 16 years after the original version 0.1 release. SciPy has become a de facto standard for leveraging scientific algorithms in the Python programming language, with more than 600 unique code contributors, thousands of dependent packages, over 100,000 dependent repositories, and millions of downloads per year. This includes usage of SciPy in almost half of all machine learning projects on GitHub, and usage by high profile projects including LIGO gravitational wave analysis and creation of the first-ever image of a black hole (M87). The library includes functionality spanning clustering, Fourier transforms, integration, interpolation, file I/O, linear algebra, image processing, orthogonal distance regression, minimization algorithms, signal processing, sparse matrix handling, computational geometry, and statistics. In this work, we provide an overview of the capabilities and development practices of the SciPy library and highlight some recent technical developments., Comment: Article source data is available here: https://github.com/scipy/scipy-articles

Published
2020
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16. Discovering Relationships between OSDAs and Zeolites through Data Mining and Generative Neural Networks

Author

Ministerio de Economía y Competitividad (España), Jensen, Z, Kwon, S., Schwalbe-Koda, Daniel, Paris Carrizo, Cecilia Gertrudis, Gomez-Bombarelli, Rafael, Román-Leshkov, Y., Corma, Avelino, Moliner Marín, Manuel, Olivetti, E. A., Ministerio de Economía y Competitividad (España), Jensen, Z, Kwon, S., Schwalbe-Koda, Daniel, Paris Carrizo, Cecilia Gertrudis, Gomez-Bombarelli, Rafael, Román-Leshkov, Y., Corma, Avelino, Moliner Marín, Manuel, and Olivetti, E. A.

Abstract

Organic structure directing agents (OSDAs) play a crucial role in the synthesis of micro-and mesoporous materials especially in the case of zeolites. Despite the wide use of OSDAs, their interaction with zeolite frameworks is poorly understood, with researchers relying on synthesis heuristics or computationally expensive techniques to predict whether an organic molecule can act as an OSDA for a certain zeolite. In this paper, we undertake a data-driven approach to unearth generalized OSDA-zeolite relationships using a comprehensive database comprising of 5,663 synthesis routes for porous materials. To generate this comprehensive database, we use natural language processing and text mining techniques to extract OSDAs, zeolite phases, and gel chemistry from the scientific literature published between 1966 and 2020. Through structural featurization of the OSDAs using weighted holistic invariant molecular (WHIM) descriptors, we relate OSDAs described in the literature to different types of cage-based, small-pore zeolites. Lastly, we adapt a generative neural network capable of suggesting new molecules as potential OSDAs for a given zeolite structure and gel chemistry. We apply this model to CHA and SFW zeolites generating several alternative OSDA candidates to those currently used in practice. These molecules are further vetted with molecular mechanics simulations to show the model generates physically meaningful predictions. Our model can automatically explore the OSDA space, reducing the amount of simulation or experimentation needed to find new OSDA candidates.

Published
2021

17. A priori control of zeolite phase competition and intergrowth with high-throughput simulations

Author

Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), Schwalbe-Koda, Daniel, Kwon, S., Paris Carrizo, Cecilia Gertrudis, Bello Jurado, Estefanía, Jensen, Z, Olivetti, E., Willhammar, Tom, Corma, Avelino, Román-Leshkov, Y., Moliner Marín, Manuel, Gomez-Bombarelli, Rafael, Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), Schwalbe-Koda, Daniel, Kwon, S., Paris Carrizo, Cecilia Gertrudis, Bello Jurado, Estefanía, Jensen, Z, Olivetti, E., Willhammar, Tom, Corma, Avelino, Román-Leshkov, Y., Moliner Marín, Manuel, and Gomez-Bombarelli, Rafael

Abstract

Zeolites are versatile catalysts and molecular sieves with large topological diversity, but managing phase competition in zeolite synthesis is an empirical, labor-intensive task. In this work, we controlled phase selectivity in templated zeolite synthesis from first principles by combining high-throughput atomistic simulations, literature mining, human-computer interaction, synthesis, and characterization. Proposed binding metrics distilled from more than 586,000 zeolite-molecule simulations reproduced the extracted literature and rationalized framework competition in the design of organic structure-directing agents. Energetic, geometric, and electrostatic descriptors of template molecules were found to regulate synthetic accessibility windows and aluminum distributions in pure-phase zeolites. Furthermore, these parameters allowed us to realize an intergrowth zeolite through a single bi-selective template. The computation-first approach enables control of both zeolite synthesis and structure composition using a priori theoretical descriptors.

Published
2021

19. Chemical, electronic, and magnetic structure of LaFeCoSi alloy: Surface and bulk properties.

Author

Lollobrigida, V., Basso, V., Borgatti, F., Torelli, P., Kuepferling, M., Coïsson, M., Olivetti, E. S., Celegato, F., Tortora, L., Stefani, G., Panaccione, G., and Offi, F.

Subjects
MAGNETIC structure, CRYSTALLOGRAPHY, ELECTRONICS, MAGNETIC properties, COLD (Temperature)
Abstract

We investigate the chemical, electronic, and magnetic structure of the magnetocaloric LaFeCoSi compound with bulk and surface sensitive techniques. We put in evidence that the surface retains a soft ferromagnetic behavior at temperatures higher than the Curie temperature of the bulk due to the presence of Fe clusters at the surface only. This peculiar magnetic surface effect is attributed to the exchange interaction between the ferromagnetic Fe clusters located at the surface and the bulk magnetocaloric alloy, and it is used here to monitor the magnetic properties of the alloy itself. [ABSTRACT FROM AUTHOR]

Published
2014
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20. A Machine Learning Approach to Zeolite Synthesis Enabled by Automatic Literature Data Extraction

Author

Ministerio de Economía y Competitividad (España), Jensen, Z, Kim, E., Kwon, S., Gani, T.Z.H., Román-Leshkov, Y., Moliner Marín, Manuel, Corma, Avelino, Olivetti, E., Ministerio de Economía y Competitividad (España), Jensen, Z, Kim, E., Kwon, S., Gani, T.Z.H., Román-Leshkov, Y., Moliner Marín, Manuel, Corma, Avelino, and Olivetti, E.

Abstract

Zeolites are porous, aluminosilicate materials with many industrial and >green> applications. Despite their industrial relevance, many aspects of zeolite synthesis remain poorly understood requiring costly trial and error synthesis. In this paper, we create natural language processing techniques and text markup parsing tools to automatically extract synthesis information and trends from zeolite journal articles. We further engineer a data set of germanium-containing zeolites to test the accuracy of the extracted data and to discover potential opportunities for zeolites containing germanium. We also create a regression model for a zeolite's framework density from the synthesis conditions. This model has a cross-validated root mean squared error of 0.98 T/1000 Å , and many of the model decision boundaries correspond to known synthesis heuristics in germanium-containing zeolites. We propose that this automatic data extraction can be applied to many different problems in zeolite synthesis and enable novel zeolite morphologies.

Published
2019

22. The HLA System in Italy

Author

Olivetti, E., Rendine, S., Cappello, N., Curtoni, E.S., and Piazza, A.

Published
1986

25. APPLICATION OF PHOTOGRAMMETRY TO BRAIN ANATOMY

Author

Nocerino, E., primary, Menna, F., additional, Remondino, F., additional, Sarubbo, S., additional, De Benedictis, A., additional, Chioffi, F., additional, Petralia, V., additional, Barbareschi, M., additional, Olivetti, E., additional, and Avesani, P., additional

Published
2017
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26. Bayesian estimation of directed functional coupling from brain recordings

Author

Benozzo, D., Jylänki, P.P., Olivetti, E., Avesani, P., Gerven, M.A.J. van, Benozzo, D., Jylänki, P.P., Olivetti, E., Avesani, P., and Gerven, M.A.J. van

Abstract

Contains fulltext : 173085.pdf (publisher's version ) (Open Access), In many fields of science, there is the need of assessing the causal influences among time series. Especially in neuroscience, understanding the causal interactions between brain regions is of primary importance. A family of measures have been developed from the parametric implementation of the Granger criteria of causality based on the linear autoregressive modelling of the signals. We propose a new Bayesian method for linear model identification with a structured prior (GMEP) aiming to apply it as linear regression method in the context of the parametric Granger causal inference. GMEP assumes a Gaussian scale mixture distribution for the group sparsity prior and it enables flexible definition of the coefficient groups. Approximate posterior inference is achieved using Expectation Propagation for both the linear coefficients and the hyperparameters. GMEP is investigated both on simulated data and on empirical fMRI data in which we show how adding information on the sparsity structure of the coefficients positively improves the inference process. In the same simulation framework, GMEP is compared with others standard linear regression methods. Moreover, the causal inferences derived from GMEP estimates and from a standard Granger method are compared across simulated datasets of different dimensionality, density connection and level of noise. GMEP allows a better model identification and consequent causal inference when prior knowledge on the sparsity structure are integrated in the structured prior.

Published
2017

28. Life cycle assessment of rare earth production from monazite

Author

Kirchain, RE, Blanpain, B, Meskers, C, Olivetti, E, Apelian, D, Howarter, J, Kvithyld, A, Mishra, B, Neelameggham, NR, Spangenberger, J, Browning, C, Northey, S, Haque, N, Bruckard, W, Cooksey, M, Kirchain, RE, Blanpain, B, Meskers, C, Olivetti, E, Apelian, D, Howarter, J, Kvithyld, A, Mishra, B, Neelameggham, NR, Spangenberger, J, Browning, C, Northey, S, Haque, N, Bruckard, W, and Cooksey, M

Abstract

The environmental life cycle impacts of conceptual rare earth production processes were assessed. An average greenhouse gas emission of 65.4 kg CO2e/kg was estimated for the 15 rare earths produced from monazite, ranging from 21.3 kg CO2e/kg for europium to 197.9 kg CO2e/kg for yttrium. The average water consumption of rare earth production was 11,170 kg/kg ranging from 3,803 kg/kg for samarium and gadolinium to 29,902 kg/kg for yttrium. The average gross energy requirement for production was 917 MJ/kg, ranging from 311 MJ/kg for samarium and gadolinium to 3,401 MJ/kg for yttrium. Given the low concentration of HREE in monazite, the high impacts across all categories for yttrium and other HREE are not necessarily representative of HREE sourced from all rare earth resources. Further studies into other rare earth mineral resources (e.g. bastnasite and xenotime) are recommended to improve the overall understanding of environmental impacts from rare earth production.

Published
2016

30. 4f charge-density deformation and magnetostrictive bond strain observed in amorphous TbFe2 by x-ray absorption spectroscopy

Author

Pascarelli, Sakura, Ruffoni, M. P., Trapananti, Angela, Mathon, Olivier, Detlefs, Carsten, Pasquale, M., Magni, A., Sasso, C. P., Celegato, F., Olivetti, E., Joly, Yves, Givord, Dominique, European Synchrotron Radiation Facility (ESRF), Istituto Nazionale di Ricerca Metrologica (INRiM), Surfaces, Interfaces et Nanostructures (SIN), Institut Néel (NEEL), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), and Micro et NanoMagnétisme (MNM)

Subjects
EXAFS, Magnetostriction, TbFe2, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], XANES
Abstract

4 pages; International audience; The giant magnetostriction observed in rare-earth transition-metal compounds such as Terfenol-D (Tb0.3Dy0.7Fe2) is commonly associated with the huge anisotropy of the 4f electron cloud. We report here the experimental observation of this phenomenon at the atomic scale, in amorphous matter. By using extended x-ray absorption fine structure spectroscopy in a differential mode, the bond strains resulting from the coupling between the anisotropic shape of the Tb 4f charge density and the environment crystalline electric field are measured. In a-TbFe2 we measure Fe-Fe and Fe-Tb bond contractions equal to 6(1)x10−4 Å and of 9(2) x10−4 Å, respectively. These are the smallest atomic displacements ever detected in amorphous matter.

Published
2010
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31. Measurement of Individual Bond Magnetostrictive Strain in α-TbFe2

Author

Pascarelli, S, Ruffoni, MP, Trapananti, A, Mathon, O, Pasquale, M, Magni, A, Sasso, CP, Celegato, F, Olivetti, E, Joly, Y, and Givord, D

Abstract

The structural changes exhibited by materials in response to their surroundings is of fundamental importance across countless disciplines in science and engineering. In the field of transducer technologies, strain-inducing phenomena (such as magnetostriction) are utilised in their own right, and form the physical foundation for sensor and actuator devices. Knowledge of their origin, and how they manifest themselves in different materials, underpins the development of new transducers and the optimisation of existing technologies. Yet in spite of this, direct measurement of a material’s intrinsic magnetostriction – the strain induced between individual atoms at a microscopic level – has proven elusive. This has essentially been due to the difficulty in measuring atomic motion with sufficient precision. In most materials, magnetostrictive atomic displacements saturate at just a few femtometres. Here, even sensitive atomic probes, such as x-ray absorption spectroscopy (XAS), lack the resolution to observe this motion by some two orders of magnitude. As a result, common experiments employ strain gauges on macroscopic samples, where the strain is easier to detect, but where atomic information is lost. However, with the recent development of differential XAS (DiffXAS) at the European Synchrotron Radiation Facility (ESRF), such atomic-scale measurements have become possible [1,2]. Initial studies into the magnetostriction of FeCo thin films demonstrated a sensitivity to femtometre scale motion [1]. Subsequent work extended this study to investigate the magnetoelastic coupling of FeCo under applied hydrostatic pressure [3], and new experiments looked into the behaviour of FePt, and rare-earth iron alloys such as Fe2Tb. But the most significant study conducted to date has been that of the Fe-Ga system [4,5]. In recent years, binary metal alloys such as Fe-Al or Fe-Ga, have attracted considerable interest [6]. It is well known that pure Fe exhibits only an extremely small magnetostriction, but when alloyed with certain nonmagnetic metallic elements, it can be enhanced by over an order of magnitude. Compositions of Fe-Ga with around 19at% Ga have reported strains of up to 400 ppm [7]. Although this doesn’t constitute a truly ‘giant’ magnetostriction, it is of interest for device applications since Fe-Ga is devoid of expensive rare-earth components, saturates in fields of only several hundred Oersteds, and possesses more desirable mechanical properties than, say, the much studied Terfenol-D alloy. In order to identify the origin of this enhancement, we took a splat-cooled foil of Fe81Ga19 and measured its Joule saturation magnetostriction with DiffXAS [4]. Unlike conventional macroscopic measurements that describe the sample as a whole, magnetostriction coefficients provided by DiffXAS describe the strain of just the first two or three atomic coordination shells surrounding a photo-excited atom. Furthermore, since it is possible to tune the x-ray energy, and so select which atom in the material is excited, it is possible to look at the strain in the local environment of each atomic species separately. Contributions from different types of bond within the structure may then be decoupled and analysed. Such fundamental information has immense value when attempting to verify theoretical models. In 2002, Wu [8] proposed a model for the magnetostriction of FexGa(1-x) that suggested a tetragonal “B2-like” structure in the vicinity of the Ga atoms was responsible for the observed enhancement. More recently, Cullen et al. [9] reached a similar conclusion, and stated that such a structure could be formed by Ga pairs randomly arranged throughout the material. Conventional XAS studies have confirmed the presence of these Ga pairs [5], but it is DiffXAS that describes how they influence the magnetostriction. From our DiffXAS spectra, we extracted the strain present in different types of bond, and with a subsequent analysis, solved the magnetostriction tensor for the material. This provided two sets of magnetostriction coefficients. In the environment around Fe, (3/2)100 = 40ppm and (3/2)111 = -32ppm, and in the environment around Ga, (3/2)100 = 390ppm and (3/2)111 ~0ppm. This demonstrates that the observed enhancement is dominated by strain in the vicinity of the Ga atoms. Furthermore, our analysis revealed that the strain in the Ga pairs was negligible, indicating that they do not contribute directly to the enhanced magnetostriction, but rather mediate the enhancement in the surrounding Ga-Fe bonds. Further experiments are planned to examine the full range of compositions over which magnetostriction enhancement is observed in this system, and, with the use of single crystal samples, investigate how the microscopic magnetostriction scales up to that seen macroscopically. [1] R.F. Pettifer, O. Mathon, S. Pascarelli, M.D. Cooke, M.R. J. Gibbs, Nature 435, 79 (2005) [2] M. P. Ruffoni, R.F. Pettifer, S. Pascarelli et al., AIP Conf. Proc. No. 882, 838 (2007) [3] S. Pascarelli, M. P. Ruffoni, A. Trapananti et al., Phys. Rev. Lett. 99, 237204 (2007) [4] M. P. Ruffoni, S. Pascarelli, R. Grössinger et al., Phys. Rev. Lett. 101, 147202 (2008) [5] S. Pascarelli, M. P. Ruffoni, R. Sato-Turtelli et al., Phys. Rev. B 77, 184406 (2008) [6] E. M. Summers, T. A. Lograsso, M. Wun-Fogle, J. Mater. Sci. 42, 9582 (2007) [7] A. E. Clark, A. B. Hathaway, M. Wun-Fogle et al., J. Appl. Phys. 93, 8621 (2003) [8] R. Wu, J. Appl. Phys. 91, 7358 (2002) [9] J. Cullen, P. Zhao, M. Wuttig, J. Appl. Phys. 101, 123922 (2007) Submitted version

Published
2009

39. Heterogeneous nucleation and heat flux avalanches in La(Fe, Si)13 magnetocaloric compounds near the critical point.

Author

Bennati, C., Gozzelino, L., Olivetti, E. S., and Basso, V.

Subjects
LANTHANUM compounds, IRON-silicon alloys, HETEROGENOUS nucleation, HEAT flux, MAGNETOCALORIC effects, CRITICAL point (Thermodynamics), MAGNETORESISTANCE
Abstract

The phase transformation kinetics of LaFe11.41Mn0.30Si1.29-H1.65 magnetocaloric compound is addressed by low rate calorimetry experiments. Scans at 1 mK/s show that its first order phase transitions are made by multiple heat flux avalanches. Getting very close to the critical point, when the transition becomes of the second order type, the step-like discontinuous behaviour associated with avalanches is smoothed out and the thermal hysteresis disappears. This result is confirmed by magneto-resistivity measurements and allows to obtain accurate values of the temperature hysteresis (ΔThyst=0.37 K) at zero external magnetic field and of the critical field (Hc=1.19 T). The number and magnitude of heat flux avalanches change as the magnetic field strength is increased, showing the interplay between the intrinsic energy barrier between phases and the microstructural disorder of the sample. [ABSTRACT FROM AUTHOR]

Published
2016
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