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2. Associated forms of binary quartics and ternary cubics

Author

Alper, J., Isaev, A. V., and Kruzhilin, N. G.

Subjects
Mathematics - Algebraic Geometry, Mathematics - Commutative Algebra, Mathematics - Complex Variables, 14L24, 14H52, 14N05, 13A50, 32S25
Abstract

Let ${\mathcal Q}_n^d$ be the vector space of forms of degree $d\ge 3$ on ${\mathbb C}^n$, with $n\ge 2$. The object of our study is the map $\Phi$, introduced in papers [EI], [AI1], that assigns every nondegenerate form in ${\mathcal Q}_n^d$ the so-called associated form, which is an element of ${\mathcal Q}_n^{n(d-2)*}$. We focus on two cases: those of binary quartics ($n=2$, $d=4$) and ternary cubics ($n=3$, $d=3$). In these situations the map $\Phi$ induces a rational equivariant involution on the projectivized space ${\mathbb P}({\mathcal Q}_n^d)$, which is in fact the only nontrivial rational equivariant involution on ${\mathbb P}({\mathcal Q}_n^d)$. In particular, there exists an equivariant involution on the space of elliptic curves with nonvanishing $j$-invariant. In the present paper, we give a simple interpretation of this involution in terms of projective duality. Furthermore, we express it via classical contravariants.

Published
2014

3. Artin algebraization for pairs with applications to the local structure of stacks and Ferrand pushouts

Author

Alper, J, Hall, J, Halpern-Leistner, D, Rydh, D, Alper, J, Hall, J, Halpern-Leistner, D, and Rydh, D

Abstract

We give a variant of Artin algebraization along closed subschemes and closed substacks. Our main application is the existence of étale, smooth or syntomic neighborhoods of closed subschemes and closed substacks. In particular, we prove local structure theorems for stacks and their derived counterparts and the existence of henselizations along linearly fundamental closed substacks. These results establish the existence of Ferrand pushouts, which answers positively a question of Temkin–Tyomkin.

Published
2024

8. Synthesis of advanced nanomaterials for Energy Applications by Laser Pyrolysis

Author

Boime, N., Desrues, A., Belchi, R., Habert, A., Porterat, D., Alper, J., Bouclé, J., Franger, S., Haon, C., Laboratoire Edifices Nanométriques (LEDNA), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Laboratoire d'Innovation pour les Technologies des Energies Nouvelles et les nanomatériaux (LITEN), Institut National de L'Energie Solaire (INES), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM.MATE]Chemical Sciences/Material chemistry
Abstract

International audience; Laser pyrolysis is an effective method to synthesize a variety of oxide and non-oxide nanoparticles such as SiC, Si, TiO2, etc. This paper will present one example each of oxide and non-oxide materials being studied in our labs, describing both their synthesis methods and applications. First, we will discuss silicon and silicon alloy core-shell nanoparticles and their performance as anode materials in Li-ion batteries. Next we will cover TiO2-carbon nanocomposites as active materials in perovskite solar cells. Due to increasing demand in energy storage, much attention has been paid to Si as an anode material in Li-Ion batteries because of its theoretical capacity (3579 mAh/g in the Li15Si4 alloy vs 372 mAh/g for graphitic carbon). However, silicon suffers several drawbacks, including rapid pulverization and continuous ripening of the solid-electrolyte interphase, limiting its use. Nanostructuration and protection of silicon by a carbon coating are proven methods to improve the behavior of the silicon-based anodes. We will present the development of a two stage laser pyrolysis reactor, wherein the continuous synthesis of silicon-carbon core-shell nanoparticles was achieved. That is, there are no intermediate manipulations between the synthesis of the core (from silane precursor) and the shell (from ethylene). The protective influence of the carbon coating is clearly seen by impedance spectroscopy. Another strategy to enhance the performance and lifetime of of Si-based anode materials is the use of Si alloys. By adding germane in the reaction zone, we were able to synthesize nanoparticles of SixGe1-x with x in the range 20-80. These particles also present a core@shell organization with a silicon shell at the surface of the alloy particle. Li-ion coin cells incorporating these materials demonstrate improved coulombic efficiency and stability.

Published
2020

12. Ex-situ solid electrolyte interphase synthesis via radiolysis of Li-ion battery anode-electrolyte system for improved coulombic efficiency

Author

Varenne, Fanny, Ortiz, D., Alper, J, Miserque, F., Boulineau, A, Martin, J.-F, Franger, S., Herlin-Boime, N., Mostafavi, M., Le Caer, S., Laboratoire Interdisciplinaire sur l'Organisation Nanométrique et Supramoléculaire (LIONS), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Edifices Nanométriques (LEDNA), Laboratoire de Réactivité des Surfaces et des Interfaces (LRSI), Département de Physico-Chimie (DPC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Innovation pour les Technologies des Energies Nouvelles et les nanomatériaux (LITEN), Institut National de L'Energie Solaire (INES), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Laboratoire de Chimie Physique D'Orsay (LCPO), and Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM.MATE]Chemical Sciences/Material chemistry
Abstract

International audience; Lithium-ion batteries (LIBs) are very efficient energy storage devices. Recently we demonstrated that the highly reactive species generated by radiolysis of an electrolyte are the same as those generated during the cycling of LIBs using similar solvents.[1.3] Furthermore, radiolysis generated these species in measurable amounts at time scales significantly shorter than electrochemical cycling in a battery cell (minutes vs. days) and enabled proposing reaction mechanisms and measuring rate constants. [1-3] The electrolytes used in LIBs are however not stable at the working potential of Li-ion anode materials. Thus, during the first cycles of the battery, the electrolyte decomposes at the anode surface producing a solid-electrolyte interphase (SEI) which is vital to device performance and safety. We have also extended the radiolysis approach to study the chemical processes at the anode-electrolyte interface and investigate ex-situ generation of SEI. Indeed, the energy cost for the SEI production is very high. For instance, days and weeks are required at the energy plant in order to form a proper SElon the surface of the anode electrodes. We have demonstrated the radiolytic growth of an SEI with a chemical composition similar to that formed during electrochemical cycling, as determined by XPS. The quantity of the SEI increases with increasing irradiation dose. Degradation products formed in the liquid and gas phase are also identified as matching those formed during electrochemical cycling. TEM results support the XPS results of increasing SEI content with increasing irradiation dose. Electrochemical characterization by galvanostatic cycling of test cells indicates that the radiolysis generated SEI greatly improves first cycle efficiency of the materials assembled in half cells, and impedance spectroscopy supports the result with an increase in resistivity observed for irradiated samples. This first study opens the door to the use of irradiation tools for the artificial generation of an SEI and for producing LIB anode materials with improved performance.

Published
2019

13. Both sides now…

Author

Campbell, N., Utting, M. R., and Alper, J.

Published
2006

15. Laser pyrolysis synthesis of nanoparticles for energy applications

Author

Desrues, Antoine, Belchi, Raphaëlle, Alper, J.-P., Boismain, Florent, Boulineau, Adrien, Coulon, P.-E., Porterat, Dominique, Habert, A., Haon, C., Bouclé, Johann, Ratier, Bernard, Franger, Sylvain, Herlin-Boime, Nathalie, Laboratoire Edifices Nanométriques (LEDNA), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Innovation pour les Technologies des Energies Nouvelles et les nanomatériaux (LITEN), Institut National de L'Energie Solaire (INES), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), RF-ELITE : RF-Electronique Imprimée pour les Télécommunications et l'Energie (XLIM-RFEI), XLIM (XLIM), Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM), Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), and Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

16. Long‐Term Safety of Rituximab in Patients With Rheumatoid Arthritis: Results of a Five‐Year Observational Study

Author

Winthrop, Kevin L., primary, Saag, Kenneth, additional, Cascino, Matthew D., additional, Pei, Jinglan, additional, John, Ani, additional, Jahreis, Angelika, additional, Haselkorn, Tmirah, additional, Furst, Daniel E., additional, Abdulky, M., additional, Abeles, M., additional, Adelglass, H., additional, Ahmed, A., additional, Alloway, J., additional, Alper, J., additional, Anand, A., additional, Anderson, J., additional, Arora, M., additional, Askari, A., additional, Baca, S., additional, Bacha, D., additional, Bagheri, S., additional, Ballou, S., additional, Bennett, R., additional, Bidula, L., additional, Blumstein, H., additional, Bognar, M., additional, Bohan, A., additional, Boniske, C., additional, Borofsky, M., additional, Box, E., additional, Braun, A., additional, Brennan, T., additional, Brent, L., additional, Cabalar, I., additional, Carteron, N., additional, Chaudhary, K., additional, Chauhan, A., additional, Cima, M., additional, Cochinwala, A., additional, Cohen, H., additional, Colburn, K., additional, Conaway, D., additional, Danning, C., additional, Dao, K., additional, Dean, J., additional, Diab, I., additional, Diegel, R., additional, Ditzian‐Kadanoff, R., additional, Dowd, J., additional, Dugowson, C., additional, Eggebeen, A., additional, El‐Kadi, H., additional, Feinberg, H., additional, Feinman, M., additional, Feinstein, J., additional, Fischer, A., additional, Foad, B., additional, Fondal, M., additional, Fraser, S., additional, Fraser, A., additional, Freeman, P., additional, Garber, M., additional, Goldstein, A., additional, Golombek, S., additional, Greenstein, N., additional, Greenwald, M., additional, Hakim, C., additional, Halla, J., additional, Hallegua, D., additional, Han, K., additional, Harris, B., additional, Hauptman, H., additional, Hirsh, J., additional, Hoffman, M., additional, Huntwork, J., additional, Husni, M., additional, Hyer, F., additional, Hymowitz, R., additional, Jones, R., additional, Kanagasegar, S., additional, Kappes, J., additional, Keating, R., additional, Kelly, G., additional, Kim, J., additional, King, C., additional, Klashman, D., additional, Knee, C., additional, Kolba, K., additional, Krick, G., additional, Krug, H., additional, Kumar, U., additional, Lakhanpal, S., additional, Lang, T., additional, Lauter, S., additional, Lawrence Ford, T., additional, Lee, W., additional, Lee, Y., additional, Leisen, J., additional, Levine, J., additional, Lidman, R., additional, Lipstate, J., additional, Malinak, J., additional, Marcus, R., additional, Martin, D., additional, Mehta, C., additional, Melton, G., additional, Metyas, S., additional, Miller, K., additional, Moidel, R., additional, Moore, C., additional, Mossell, J., additional, Munoz, G., additional, Murphy, F., additional, Nami, A., additional, Nascimento, J., additional, Neal, N., additional, Neiman, R., additional, Neuwelt, C., additional, Nguyen, P., additional, Niemer, M., additional, Oelke, K., additional, Oza, M., additional, Pachaidee, S., additional, Patel, S., additional, Pegram, S., additional, Penmetcha, M., additional, Perkins, J., additional, Perl, A., additional, Peterson, L., additional, Pittsley, R., additional, Portnoff, K., additional, Rahmani, D., additional, Raja, N., additional, Ratnoff, W., additional, Rezaian, M., additional, Rhea, C., additional, Rice, D., additional, Ridley, D., additional, Rivadeneira, A., additional, Rizzo, W., additional, Roane, G., additional, Rocca, P., additional, Rosen, M., additional, Saikali, W., additional, Saitta, M., additional, Sankoorikal, A., additional, Saway, P., additional, Schneider, P., additional, Schwartzman, S., additional, Scoville, C., additional, Shergy, W., additional, Shiel, W, additional, Shurmur, R., additional, Sikes, D., additional, Singhal, A., additional, Snyder, A., additional, Songcharoen, S., additional, Sosenko, M., additional, Soto Raices, O., additional, Stahl, N., additional, Stark, K., additional, Strachan, M., additional, Stupi, A., additional, Sullivan, N., additional, Sylvester, R., additional, Tabechian, D., additional, Tagoe, C., additional, Taylor, P., additional, Thakker, S., additional, Thakor, M., additional, Thakur, N., additional, Tidmore, W., additional, Toth, M., additional, Trostle, D., additional, Udell, J., additional, Van de Stouwe, M., additional, Venuturupalli, R., additional, Weiss, D., additional, Weselman, K., additional, Winn, D., additional, Yung, C., additional, Zable, E., additional, and Zamiri, B., additional

Published
2019
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17. Analysis of Si-based Anode in Li-ion Batteries Combining Electrochemical Characterization and Multi-Scale Modeling

Author

Bernard, P, Desrues, A, Alper, J, Dufour, N., Haon, C., Chandesris, M., Herlin-Boime, N., Laboratoire d'Innovation pour les Technologies des Energies Nouvelles et les nanomatériaux (LITEN), Institut National de L'Energie Solaire (INES), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Laboratoire Edifices Nanométriques (LEDNA), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Palacin, Serge, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Rayonnement Matière de Saclay (IRAMIS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)

Subjects
[CHIM.MATE] Chemical Sciences/Material chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry
Abstract

International audience; Due to its high capacity compared to graphite, silicon has attracted attention among li-ion batteries technology as a promising material for negative electrodes. It is abundant, not toxic. However, this material is well known to be subject to large volume changes upon lithation and delithation (up to 320 %). This phenomenon causes particles cracking, instability of the passivation layer appearing at the interface of solid Si and liquid electrolytes (SEI) and finally leads to electrode delamination, affecting the cycle performance of such batteries in particular long time performances. To overcome these problems, several strategies have been proposed such as using submicronic particles (i.e.< 150 nm) to mitigate the volume changes and/or protection of the silicon material with a carbon layer [reference]. Combining both strategies Si@C core-shell nanoparticles synthesized in one step process have recently been proposed as a promising anode material. More specifically, the Si-based nanoparticles are synthesized in a two stages laser pyrolysis reactor, which allows obtaining carbon coated silicon nanoparticles in one single step, mitigating oxidation because there is no air exposure between the synthesis of the core and shell as well as particle degradation due to nanometric size. The synthesis technique also allows controlling organization of the core, both crystalline and amorphous silicon cores have been synthesized. Moreover, the shell thickness can be varied by changing the flow of carbon precursor. To optimize the design of composite electrodes based on such active materials, an in-depth understanding of their performance and chemical/mechanical degradation processes remains critical. In this work, multi-scale modeling is developed based on the analysis of the electrochemical performances of electrodes composed of Si-based nanoparticles (with and without shell). Several electrochemical techniques such as GITT (Galvanostatic Intermittent Titration Technique), galvanostatic cycling and Electrochemical Impedance Spectroscopy (EIS) were used to characterize the battery performance. These data provide physical parameters to feed a mathematical model (Newman) of the Si electrode based on the porous-electrode theory. This Newman model combines description at the nanoparticle scale up to the composite electrode scale. Besides, the EIS study, carried out at various cell states of lithiation of Si material, allows tracking the evolution of several critical parameters (for example SEI resistance, charge transfer resistance at the interface) of the mathematical model (figure 1). Figure 1b shows the evolution of the exchange current density with SOC for coated and non-coated materials together with the expected theoretical evolution with constant kinetic rate evidencing the need for an accurate modelling. This presentation will be devoted to our first results concerning such a modelling and application to the multiscale behavior of coated as well as non-coated silicon as active anode materials.

Published
2017

18. Laser pyrolysis for the controlled synthesis of amorphous or crystalline Si@C nanoparticles - Material Synthesis and Performance Characterization in Li-Ion batteries

Author

Alper, J, Boismain, F, Sourice, J, Porcher, W, Foy, E, Habert, Aurélie, de Vito, Eric, Reynaud, C, Haon, C, Herlin-Boime, N, Laboratoire Edifices Nanométriques (LEDNA), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Laboratoire d'Innovation pour les Technologies des Energies Nouvelles et les nanomatériaux (LITEN), Institut National de L'Energie Solaire (INES), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Laboratoire Archéomatériaux et Prévision de l'Altération (LAPA - UMR 3685), IRAMAT - Laboratoire Métallurgies et Cultures (IRAMAT - LMC), Institut de Recherches sur les Archéomatériaux (IRAMAT), Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université Bordeaux Montaigne-Université de Technologie de Belfort-Montbeliard (UTBM)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université Bordeaux Montaigne-Université de Technologie de Belfort-Montbeliard (UTBM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-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)-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-Centre National de la Recherche Scientifique (CNRS)-Université de Technologie de Belfort-Montbeliard (UTBM)-Université d'Orléans (UO)-Université Bordeaux Montaigne-Centre National de la Recherche Scientifique (CNRS), and Palacin, Serge

Subjects
[CHIM.MATE] Chemical Sciences/Material chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry
Abstract

International audience; As the world moves away from distributed fossil fuel use in order to mitigate the climatic effects of carbon pollution, the need for high energy density storage devices continues to grow. In Lithium Ion Batteries, the replacement of graphite (372 mAh.g$^{-1}$) as the anode active material by higher specific capacity materials is a strategy to meet the continuous demand for increased energy storage. Silicon appears as an attractive material because of its high theoretical specific capacity (3579 mAh.g$^{-1}$). However use of silicon based anodes has not yet been commercially realized because of rapid performance degradation due to mechanical instabilities and large volume changes upon lithiation/delithiation. Silicon nanostructuration and encapsulation in carbon have been shown to increase cycle life. In this context, core-shell silicon-carbon nanoparticles (Si@C) are promising candidates for application as LiB anode materials. Such nanoparticles were synthesized in a reactor by a continuous gas phase method, laser pyrolysis. We report here how flow simulations helped in the design of a reactor where decomposition of silane and ethylene are conducted in two successive reaction zones to produce silicon cores in the first zone and coat it with carbon in the second zone. The reactor design enables stable reactor conditions leading to the scalable single-step synthesis of amorphous or crystalline silicon nanoparticles coated with a carbon shell (a-Si@C). The advantages of the a-Si@C material are demonstrated by comparison with c-Si@C material. In particular, cyclic voltammetry demonstrates that a-Si@C composite reaches maximal lithiation during the first sweep, which is attributed to the amorphous core. After 500 charge/discharge cycles, it retains a capacity of 1250 mAh.g$^{-1}$ (C/5 rate) and 800 mAh.g$^{-1}$ (2C), with a 99.95% coulombic efficiency Moreover, post-mortem observations prove formation of a limited solid electrolyte Interphase with an electrode expansion of less than 20% in volume and preserved nanostructuration within the electrode.

Published
2017

19. Characteristics of laminates with delamination control strips

Author

Sun, C. T, Goering, J. C, Alper, J. M, and Gause, L. W

Subjects
Composite Materials
Abstract

Tough resin is needed to resist delamination crack propagation. However, modulus often has to be compromised because it is difficult to retain both high modulus and toughness in a matrix material. A potential solution is to use a hybrid system in which tough resin strips are included within a conventional matrix composite. By adjusting the spacing of the tough resin strips, maximum delamination size can be controlled. Experimental results for impact damage and subsequent damage propagation in laminates containing tough resin strips are reported. Plain adhesive strips and fiber-reinforced tough resin composite strips were used in constructing the hybrid laminates. Test results indicated that size of delamination inflicted by impact was confined between the tough resin strips. As a result, significantly increased residual compressive strength was obtained. Impacted laminates containing tough resin strips were also fatigue tested. It was found that these strips reduced the growth of the impact damage area relative to the growth seen in coupons with no tough resin strips. Damage growth from an open hole under tension fatigue was evaluated using both tough resin strips and glass fiber reinforced tough resin strips. Unreinforced tough resin strips retarded delamination growth from the open hole, but did not stop matrix cracks growing in the fiber direction. Fiber reinforced tough resin strips did not contain axial delamination growth from the open hole. However, they did act as crack arresters, stopping the through-the-thickness tension crack originating from the hole.

Published
1992

21. Long-Term Safety of Rituximab in Rheumatoid Arthritis: Analysis From the SUNSTONE Registry.

Author

Winthrop, Kevin L., Saag, Kenneth, Cascino, Matthew D., Pei, Jinglan, John, Ani, Jahreis, Angelika, Haselkorn, Tmirah, Furst, Daniel E., Abdulky, M., Abeles, M., Adelglass, H., Ahmed, A., Alloway, J., Alper, J., Anand, A., Anderson, J., Arora, M., Askari, A., Baca, S., and Bacha, D.

Abstract

Objective: To evaluate the long-term safety of rituximab in an observational cohort of patients with rheumatoid arthritis (RA) who had an inadequate response to ≥ 1 antitumor necrosis factor therapies in the United States (SUNSTONE Registry).Methods: In this prospective, observational cohort study, patients received rituximab according to their physician's standard practice and were evaluated at standard-of-care follow-up visits at least every 6 months. The primary outcome was the incidence of protocol-defined significant infections. Secondary outcomes included serious adverse events potentially associated with rituximab, cardiovascular or thrombotic (CVT) events, seizures, deaths and pregnancies. Posthoc analyses assessed outcomes by concomitant medication use.Results: Overall, 989 patients (safety-evaluable population) received ≥ 1 dose of rituximab, with a total follow-up of 3844 patient-years (PYs; mean duration, 3.9 years). In total, 341 significant infections occurred in 197 patients (19.9%). The incidence rates (95% CI) for significant infections, CVT events, and seizures were 8.87 (7.98, 9.86), 1.95 (1.56, 2.45), and 0.18 (0.09, 0.38) per 100 PYs, respectively. The incidence of significant infections did not increase with time or with cumulative rituximab exposure. During the study, 64 patients died (crude mortality [95% CI]: 1.66 per 100 PYs [1.30, 2.13]). The most common causes of death were infections (19 patients), malignancy (14), and cardiovascular events (13). Eight pregnancies were reported in 7 patients.Conclusion: In patients with RA treated with rituximab for up to 5 years, the rates of significant infections were stable over time and higher in patients who received long-term systemic steroid treatment. This article is protected by copyright. All rights reserved. [ABSTRACT FROM AUTHOR]

Published
2019
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26. Genetic discrimination and the law

Author

Natowicz, M R, Alper, J K, and Alper, J S

Subjects
Research Article
Abstract

The use of genetic tests can lead to genetic discrimination, discrimination based solely on the nature of an individual's genotype. Instances of the discriminatory uses of genetic tests by employers and insurance companies have already been reported. The recently enacted Americans with Disabilities Act of 1990 (ADA), together with other federal and state laws, can be used to combat some forms of this discrimination. In this article we define and characterize genetic discrimination, discuss the applicability of the various relevant federal and state laws, including the ADA, in the areas of employment and insurance discrimination, explore the limitations of these laws, and, finally, suggest some means of overcoming these limitations.

Published
1992

27. Oral abstracts 1: Spondyloarthropathies * O1. Detecting axial spondyloarthritis amongst primary care back pain referrals

Author

Harris, C., primary, Remedios, D., additional, Aptowitzer, T., additional, Keat, A., additional, Hamilton, L., additional, Guile, G., additional, Belkhiri, A., additional, Newman, D., additional, Toms, A., additional, Macgregor, A., additional, Gaffney, K., additional, Morton, L., additional, Jones, G. T., additional, MacDonald, A. G., additional, Downham, C., additional, Macfarlane, G. J., additional, Tillett, W., additional, Jadon, D., additional, Wallis, D., additional, Costa, L., additional, Waldron, N., additional, Griffith, N., additional, Cavill, C., additional, Korendowych, E., additional, de Vries, C., additional, McHugh, N., additional, Iaremenko, O., additional, Fedkov, D., additional, Emery, P., additional, Baeten, D., additional, Sieper, J., additional, Braun, J., additional, van der Heijde, D., additional, McInnes, I., additional, Van Laar, J., additional, Landewe, R., additional, Wordsworth, B. P., additional, Wollenhaupt, J., additional, Kellner, H., additional, Paramarta, I., additional, Bertolino, A., additional, Wright, A. M., additional, Hueber, W., additional, Sofat, N., additional, Smee, C., additional, Hermansson, M., additional, Wajed, J., additional, Sanyal, K., additional, Kiely, P., additional, Howard, M., additional, Howe, F. A., additional, Barrick, T. R., additional, Abraham, A. M., additional, Pearce, M. S., additional, Mann, K. D., additional, Francis, R. M., additional, Birrell, F., additional, Carr, A., additional, Macleod, I., additional, Ng, W.-F., additional, Kavanaugh, A., additional, Chattopadhyay, C., additional, Gladman, D., additional, Mease, P., additional, Krueger, G., additional, Xu, W., additional, Goldstein, N., additional, Beutler, A., additional, Baraliakos, X., additional, Laurent, D. D., additional, Gsteiger, S., additional, Conaghan, P. G., additional, Peterfy, C. G., additional, DiCarlo, J., additional, Olech, E., additional, Alberts, A. R., additional, Alper, J. A., additional, Devenport, J., additional, Anisfeld, A. M., additional, Troum, O. M., additional, Cooper, P., additional, Gimpel, M., additional, Deakin, G., additional, Jameson, K., additional, Godtschailk, M., additional, Gadola, S., additional, Stokes, M., additional, Cooper, C., additional, Gordon, C., additional, Kalunian, K., additional, Petri, M., additional, Strand, V., additional, Kilgallen, B., additional, Barry, A., additional, Wallace, D., additional, Flurey, C. A., additional, Morris, M., additional, Pollock, J., additional, Hughes, R., additional, Richards, P., additional, and Hewlett, S., additional

Published
2012
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29. Discrimination as a consequence of genetic testing

Author

Billings, P R, Kohn, M A, de Cuevas, M, Beckwith, J, Alper, J S, and Natowicz, M R

Subjects
Research Article
Abstract

Genetic discrimination refers to discrimination directed against an individual or family based solely on an apparent or perceived genetic variation from the "normal" human genotype. We describe here the results of a case history study designed to assess whether or not genetic discrimination exists. Using the above definition of genetic discrimination and applying stringent criteria for case selection, we find that genetic discrimination exists and is manifested in many social institutions, especially in the health and life insurance industries. Stigmatization, and denial of services or entitlements to individuals who have a genetic diagnosis but who are asymptomatic or who will never become significantly impaired, is noted. Follow-up comprehensive studies on the significance and varieties of genetic discrimination are needed. In order to avoid creating a new social underclass based on genetic discrimination (the "asymptomatic ill"), existing and future genetic testing or screening programs need review by medical, scientific, legal, and social policy experts, as well as the public, and may require modification.

Published
1992

33. Fucoidan Content in Philippine Brown Seaweeds

Author

Joemark T. Narsico, Joyce A. Nieva, Alper James G. Alcaraz, Eladio G.M. Anino V, Norchel Corcia F. Gomez, and Marco Nemesio E. Montaño

Subjects
Brown seaweeds, distribution, fucoidan, fucoidan yield, Science, Science (General), Q1-390
Abstract

This study aims to determine which brown macroalgae in the Philippines has the highest content of partially purif ied fucoidan. Percent fucoidan content of brown seaweeds Sargassum spp. , Padina sp. , Hydroclathrus sp. , Turbinaria ornata J. Agardh, Hormophyza cuneiformis PC Silva, and Dictyota dichotoma Lamouroux were determined in f ifty sites across 14 provinces in Northern Luzon (Cagayan, Ilocos), West Luzon (Pangasinan), the eastern seaboard of Luzon (Quezon Province, Camarines, Sorsogon), Central and Eastern Visayas (Bohol, Cebu, Negros Oriental, Negros Occidental), and Northern Mindanao (Camiguin, Lanao del Norte, Misamis Oriental, Misamis Occidental). Crude and semi-pure fucoidan were extracted through acid hydrolysis and ethanol precipitation using 50 grams of dried and milled seaweed biomass. Extracts were verif ied using infrared spectroscopy with fucoidan from Fucus vesiculosus as standard. Sargassum spp. is the most widely distributed source of fucoidan found in all sites. T. ornata was found in only 11 sites. Both have significantly higher percent content (p ≥ 0.05) of fucoidan than other sampled seaweeds. Higher percent content of semi-purified fucoidan were observed in D. dichotoma from Bohol (1.53%), H. cuneiformis from Cebu (2.17%), Hydroclathrus sp. from Pangasinan (2.23%), Padina sp. from Quezon Province (3.69%), Sargassum spp. from Camiguin (4.30%), and T. ornata from Cagayan (7.03%). Keywords:

Published
2018

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