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1. A compact detector system for simultaneous measurements of the light yield non-linearity and timing properties of scintillators

Author

Benoit Sabot, Chavdar Dutsov, Philippe Cassette, Krasimir Mitev, Matthieu Hamel, Guillaume H. V. Bertrand, Kheirreddine Lebbou, and Christophe Dujardin

Subjects
Medicine, Science
Abstract

Abstract This work presents an outline of a detection system that employs the Compton spectrometer method to assess the non-linearity of scintillator light yield. A novel approach is introduced, leading to more accurate measurements through the separate determination of the intrinsic light output parameters and the non-linearity of the scintillators. Key features of this system include the use of a portable scintillation detector with three photomultiplier tubes for precise measurement of the average number of detected photoelectrons and the incorporation of recent advancements in correction techniques for accidental coincidences. The integration of digital acquisition, offline data analysis, and geometric adaptation reduces the time required to perform a measurement. The developed detector can simultaneously measure different timing properties, as well as the relative intensities following ionization excitation in a scintillator. The system’s performance is demonstrated through measurements of the light yield dependence on the deposited energy for commercially available liquid, plastic, and inorganic scintillators. Such instrumentation serves as a valuable tool in the development of novel scintillating materials, including liquid or solid organic scintillators, inorganic scintillators, and composite scintillators for electron detection, in addition to traditional X-ray or $$\gamma$$ γ -ray detection.

Published
2024
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2. From Sintering to Particle Discrimination: New Opportunities in Metal–Organic Frameworks Scintillators

Author

Vincent Villemot, Nicolas Dufour, Sharvanee Mauree, Benoît Sabot, Guillaume H. V. Bertrand, and Matthieu Hamel

Subjects
densification, discrimination, MCNP, metal organic frameworks, photoluminescence, radioluminescence, Applied optics. Photonics, TA1501-1820, Optics. Light, QC350-467
Abstract

The characterization of a scintillating metal organic framework (MOF) is not straightforward, mainly due to the small size and low density of the material. In this context, we present herein a generic method to give an easy access to the determination of a key parameter in the scintillation field, namely the light output. To reach this, MOF‐205 was first synthesized as millimetric‐size single crystals then sintered under pressure and temperature conditions to afford a pellet. The density was increased by 300% while maintaining optical properties on par with scintillation application. The as‐prepared scintillator was then characterized in terms of photoluminescence (PL; UV‐excited emission spectrum, time‐correlated single photon counting) and radioluminescence (RL) spectroscopy (beta‐excited emission spectrum, alpha, beta and gamma pulse height spectra, alpha/beta and alpha/gamma discrimination). Results were compared with commercial BC‐404 plastic scintillator performances as well as supported by MCNP6.2 simulation.

Published
2022
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3. Techno-economic assessment of co-pyrolyzed kitchen waste and rice straw for co-generation of heat and power

Author

Nyambura, Samuel Mbugua, Li, Chao, Xu, Jialang, Wang, Jufei, Li, Hu, Zhang, Zhaotong, V. Bertrand, Gbenontin, Ndumia, Joseph Ndiithi, Li, Xiaolin, Atsbha, Musie Welldegerima, Chin, Bridgid, Nyambura, Samuel Mbugua, Li, Chao, Xu, Jialang, Wang, Jufei, Li, Hu, Zhang, Zhaotong, V. Bertrand, Gbenontin, Ndumia, Joseph Ndiithi, Li, Xiaolin, Atsbha, Musie Welldegerima, and Chin, Bridgid

Abstract

Increasing concerns relating to depletion of fossil fuels and global warming coupled with significant growth in waste-to-energy markets have propelled the need for ingenious and flexible technologies that can effectively transform waste biomass into fuels and power at high efficiency. In this study, a comprehensive techno-economic investigation was undertaken to investigate the economic potential of utilizing co-pyrolyzed kitchen food waste and rice straw in a waste to heat and power facility based on microwave pyrolysis and a combined heat and power system. The study involved microwave pyrolysis experiments to investigate the effects of blending proportions of kitchen food waste and rice straw on the evolution of synthetic gas components based on gas chromatography analysis. The optimal blending proportion was then used to run the Aspen Plus heat and power plant simulation. Boiler efficiency, steam cycle thermal efficiency, electrical efficiency, and overall system efficiency were 96.30 %, 36.46 %, 41.61 %, and 35.11 %, respectively. The model had an estimated annual power production of 744,576 kWh/year, hot water production capacity of 1,727,649 L/year, and annual biochar production of 162,045 kg/year. A positive net present value was observed for the project after the second year, coupled with an internal rate of return of 0.62 and a profitability index of 3.85 over ten years. The heat generated can meet rapidly increasing urban heating needs and the power will contribute to grid stabilization. Sensitivity analysis revealed that the greatest potential performance improvements can be achieved by increasing biochar selling price and reducing total investment costs and total annual operating costs. Overall, the study shows scaled-up microwave-based heat and power technology to be a profitable and effective waste management and renewable energy solution.

Published
2023

8. Tuning the decay time of liquid scintillators

Author

Krasimir Mitev, Chavdar Dutsov, Benoît Sabot, Matthieu Hamel, Guillaume H. V. Bertrand, Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), 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'Intégration des Systèmes et des Technologies (LIST), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire National Henri Becquerel (LNHB), Sofia University 'St. Kliment Ohridski', Laboratoire Capteurs Fibres Optiques (LCFO), This research was performed with financial support of National Science Fund of Bulgaria in the frame of the TDCX project, contract No KP-06-H38/9 06.12.19., Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), 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'Intégration des Systèmes et des Technologies (LIST (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Département d'instrumentation Numérique (DIN (CEA-LIST)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Subjects
fluorophore, Materials science, Photoluminescence, Liquid scintillator, Physics::Instrumentation and Detectors, Biophysics, Analytical chemistry, 02 engineering and technology, Scintillator, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 010402 general chemistry, 01 natural sciences, Biochemistry, Particle detector, chemistry.chemical_compound, Viscosity, decay time, sensor, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], nuclear instrumentation, instrumentation, Scintillation, TCSPC, Pyrene, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Toluene, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Solvent, chemistry, Radiation detection, photoluminescence, 0210 nano-technology, ionizing radiation
Abstract

International audience; The choice of an appropriate viscosity of a liquid scintillator solvent can lead to the fine tuning of its decay time. We present herein the photophysical and scintillation properties of liquid scintillators containing pyrene and 9,10-diphenylanthracene as the primary and secondary fluorophores, respectively, being dissolved either in toluene, diisopropylnaphthalene or mixtures of these two solvents. By modifying the dynamic viscosity, the photoluminescence decay time can be easily chosen in the range 40–120 ns. For all liquid scintillators the light yields were satisfying, and the scintillation decays were slightly different, ranging from 36 up to 125 ns.

Published
2021
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9. OP35 Natural history of anal ulcerations in pediatric-onset Crohn’s Disease: A population-based study

Author

P Mortreux, A Leroyer, C Dupont, D Ley, V Bertrand, C Spyckerelle, N Guillon, P Desreumaux, C Gower-Rousseau, G Savoye, M Fumery, D Turck, L Siproudhis, and H Sarter

Subjects
Gastroenterology, General Medicine
Abstract

Background Anal ulcerations are frequently observed in Crohn’s disease (CD). Their natural history remains poorly known, especially in pediatric-onset CD. The aims of this study were: to determine in a population-based study the risk of anal ulcerations in pediatric onset CD; to identify risk factors for anal ulcerations; to evaluate the risk of progression towards suppurative lesions; to evaluate the risk factors of progression towards suppurative lesions. Methods All patients with a diagnosis of CD before the age of 17 years between 1988 and 2011 within the population-based registry EPIMAD were followed retrospectively until 2013. A specific collection of additional data was performed in patients with anal ulcerations at diagnosis or during follow-up. The variables collected included: proctological examination, diagnostic management (perineal MRI, endoscopic ultrasound, examination under general anaesthesia) and treatment (medical or surgical). Multivariate Cox models were used to identify factors associated with anal ulcerations and factors of progression towards suppurative lesions. An adjusted time-dependent Cox model was used to evaluate the risk of progression of anal ulcerations towards suppurative lesions. Results 1005 patients were included (females, 450 (44.8%); median age at diagnosis 14.4 years (IQR, 12.0–16.1)). 257 (25.6%) had anal ulceration at diagnosis. Cumulative incidence of anal ulceration at 5 and 10 years from diagnosis was 38.4% (CI95%, 35.2–41.4) and 44.0% (CI95%, 40.5–47.2). The presence of extra-intestinal manifestations (HR 1.46, CI95% 1.19–1.80, p=0.0003) and upper digestive location (HR 1.51, CI95% 1.23–1.86, p In patients with anal ulceration, the diagnostic period (before or since the “biologic era”), exposure to immunosuppressants and/or anti-TNF did not influence the risk of perianal suppuration. Conclusion Anal ulceration is frequent in pediatric-onset CD, with nearly half of patients presenting with at least one episode after 10 years of evolution. Perianal suppurations are twice as frequent in patients with present or past anal ulceration. These results plead for a proactive therapeutic approach in case of anal ulcerations.

Published
2022
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10. Correction: Tuning trion binding energy and oscillator strength in a laterally finite 2D system: CdSe nanoplatelets as a model system for trion properties

Author

Sabrine Ayari, Michael T. Quick, Nina Owschimikow, Sotirios Christodoulou, Guillaume H. V. Bertrand, Mikhail Artemyev, Iwan Moreels, Ulrike Woggon, Sihem Jaziri, and Alexander W. Achtstein

Subjects
General Materials Science
Abstract

Correction for ‘Tuning trion binding energy and oscillator strength in a laterally finite 2D system: CdSe nanoplatelets as a model system for trion properties’ by Sabrine Ayari et al., Nanoscale, 2020, 12, 14448–14458, DOI: 10.1039/D0NR03170D.

Published
2021

13. Design of a High-Power UWB Antenna Incorporating a Solid Dielectric for Electronic Warfare Applications

Author

Edson Martinod, Romain Negrier, V. Bertrand, Michèle Lalande, Jeremy Hyvernaud, and Joël Andrieu

Subjects
Materials science, Explosive material, Article Subject, business.industry, Bandwidth (signal processing), Dielectric, Marx generator, TK1-9971, Rise time, Electric field, HE9713-9715, Optoelectronics, Breakdown voltage, Electrical engineering. Electronics. Nuclear engineering, Electrical and Electronic Engineering, Antenna (radio), business, Cellular telephone services industry. Wireless telephone industry
Abstract

In this paper, a high-power ultrawideband antenna is presented for the purpose of remotely neutralizing improvised explosive devices. The developed antenna has a bandwidth between 230 MHz and 2 GHz, as well as a maximum realized gain of 18.7 dB. The antenna structure incorporates a solid dielectric (HDPE 1000) so that it can be powered, without risk of a possible breakdown voltage, by a Marx generator which delivers a bipolar pulse with a peak amplitude of +/−250 kV, a rise time of 170 ps, and a duration of 1 ns. The radiated electric field obtained in simulation is, respectively, 1 MV/m peak and 126 kV/m peak at a distance of 1 m and 10 m.

Published
2021
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14. 6Li210B4O7 NPs-loaded plastic scintillators for fast/thermal neutron and gamma ray detection

Author

Jonathan Dumazert, Clément Lynde, Guillaume H. V. Bertrand, Eva Montbarbon, Amélie Grabowski, Matthieu Hamel, Romain Coulon, Camille Frangville, and Amélie Venerosy

Subjects
Materials science, Radiochemistry, Nanoparticle, Context (language use), 02 engineering and technology, Scintillator, Thermal neutron detection, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Neutron temperature, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Materials Chemistry, General Materials Science, Polystyrene, POPOP, 0210 nano-technology, Gamma ray detection
Abstract

We report herein the synthesis of a new series of plastic scintillators (PSs) loaded with 6Li210B4O7 nanoparticles (NPs), as new radioluminescent sensors for fast/thermal neutron and gamma ray detection in the critical context of homeland security. This study aims to evaluate the benefit of such nanoparticles towards thermal neutron detection in a fast neutrons/gamma discriminating PS composition. First, a size-controlled synthesis of Li2B4O7 NPs assited with poly(N-vinylpyrrolidone) (PVP) is performed. Then enriched 6Li210B4O7 NPs (65 ± 22 nm) are dispersed in clear PSs mainly composed of polystyrene and standard fluorophores (20 wt% PPO, 0.03 wt% POPOP). For the first time, a triple nthermal/nfast/gamma discrimination is presented with a NP-loaded plastic scintillator, where both 6Li(n,α) and 10B(n,α) are observed.

Published
2019
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15. Large solubility of lithium carboxylates reaching high rates of 6Li incorporation in polystyrene-based plastic scintillators for fast/thermal neutron and gamma ray detection

Author

Guillaume H. V. Bertrand, Clément Lynde, Eva Montbarbon, Amélie Grabowski, Camille Frangville, and Matthieu Hamel

Subjects
Materials science, Gamma ray, Analytical chemistry, chemistry.chemical_element, 02 engineering and technology, Scintillator, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Neutron temperature, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Methacrylic acid, Materials Chemistry, General Materials Science, Lithium, Polystyrene, Solubility, POPOP, 0210 nano-technology
Abstract

6Li-Doped plastic scintillators (PSs) have been optimized as radioluminescent sensors for detection of fast/thermal neutrons and gamma rays for several purposes such as homeland security. Among 16 low molecular weight (C < 8) lithium carboxylates, Liα-valerate (LiαVal) exhibits high potential for loading (up to 50 wt%) in clear PSs composed of polystyrene and standard fluors (20 wt% PPO, 0.03 wt% POPOP). A methodical study of PS composition illustrates that the Li carboxylates and methacrylic acid comonomers impact the scintillation yields (from 4410 to 7790 ph per MeV) and nthermal/nfast/gamma discrimination performances with significant figures of merit (from 0.23 to 1.45 above 180 keVee).

Published
2019
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16. Unravelling the true MOF-5 luminescence

Author

Isabelle Leray, Robert Pansu, Vincent Villemot, Guillaume H. V. Bertrand, Matthieu Hamel, Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), 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'Intégration des Systèmes et des Technologies (LIST), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire Lumière, Matière et Interfaces (LuMIn), CentraleSupélec-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Ecole Normale Supérieure Paris-Saclay (ENS Paris Saclay), Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), Institut de Chimie du CNRS (INC)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Ecole Normale Supérieure Paris-Saclay (ENS Paris Saclay), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), and 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'Intégration des Systèmes et des Technologies (LIST (CEA))

Subjects
phase-pure material, Photoluminescence, Materials science, Fluorophore, Zn4O, General Chemical Engineering, 010402 general chemistry, Metal–organic framework (MOF), 01 natural sciences, electronic transitions, chemistry.chemical_compound, luminescence, time-correlated single photon counting (TCSPC), Spectroscopy, Instrumentation, Photoluminescence spectroscopy, 010405 organic chemistry, fluorophore stabilization, General Chemistry, Fluorescence, Photon counting, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry, Atomic electron transition, Chemical physics, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, fluorescence, single crystal, Luminescence, Single crystal, moisture sensitivity
Abstract

International audience; Highly pure millimeter-sized MOF-5 single crystals were synthesized and characterized. Photoluminescence (PL) spectroscopy and time-correlated single photon counting (TCSPC) demonstrate a solvent-guest dependency of MOF-5 emission and its ligand-centred nature. These results allowmeasuring the true MOF-5 luminescence free of solvent at a wavelength of 355 nm, a significantly lower wavelength than previously published. MOF-5 emission was also evaluated with different solvents and various degrees of water intake, explaining previously published observations. Comparison between lifetimes shows the fluorophore stabilization within the frameworks and demonstrates the progressive influence of the Zn4O subunits on the fluorescence during hydration. Overall, this work highlights the necessity to obtain phase-pure material, especially when moisture sensitivity can play a role, before ascribing electronic transitions. This study is a rigorous new take on the iconic MOF-5 and on its photoluminescence properties.

Published
2020
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17. Le Trillat assisté par arthroscopie dans le traitement de l’instabilité antérieure de l’épaule

Author

Ludovic Labattut, P.Y. Reybet Degat, Pierre Trouilloud, Pierre Martz, Marc Arcens, Emmanuel Baulot, and V. Bertrand

Subjects
030222 orthopedics, 03 medical and health sciences, 0302 clinical medicine, Orthopedics and Sports Medicine, Surgery, 030229 sport sciences
Abstract

Resume La technique de Trillat a ciel ouvert a demontre son efficacite dans le traitement de l’instabilite anterieure d’epaule, tant pour prevenir la recidive que pour permettre une bonne recuperation des amplitudes articulaires. Nous decrivons ici une adaptation arthroscopique de cette technique et nos premiers resultats cliniques. Pour les 18 patients que nous avons operes entre 2011 et 2014, au suivi moyen de 2 ans (24,7 ± 9,8 mois), les resultats cliniques etaient tres satisfaisants avec un score de Walch–Duplay a 81,5 ± 18, un score de Rowe de 83,6 ± 16 et 94 % de patients satisfaits ou tres satisfaits avec une duree operatoire de 55 ± 13 min. Nous ne notons aucune recidive. Ainsi, par sa facilite de realisation et ses bons resultats cliniques, cette adaptation arthroscopique constitue une alternative simple et reproductible aux butees arthroscopiques, qui restent actuellement reservees a des equipes expertes.

Published
2018
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18. A Transient UWB Antenna Array Used with Complex Impedance Surfaces

Author

A. Godard, L. Desrumaux, V. Bertrand, J. Andrieu, M. Lalande, B. Jecko, V. Couderc, M. Brishoual, and R. Guillerey

Subjects
Electrical engineering. Electronics. Nuclear engineering, TK1-9971, Cellular telephone services industry. Wireless telephone industry, HE9713-9715
Abstract

The conception of a novel Ultra-Wideband (UWB) antenna array, designed especially for transient radar applications through the frequency band (300 MHz–3 GHz), is proposed in this paper. For these applications, the elementary antenna must be compact and nondispersive, and the array must be able to steer in two dimensions. The geometry of the elementary antenna and its radiation characteristics are presented. The array beam steering is analyzed and a technique making the increase of the transient front-to-back ratio possible is described.

Published
2010
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19. P624 Long-term effectiveness of anti-TNF therapy in pediatric-onset inflammatory bowel diseases: a population-based study

Author

M Fumery, G Savoye, D Ley, C Dupont, V Bertrand, C Spyckerelle, N Guillon, P Desreumaux, C Gower-Rousseau, H Sarter, D Turck, and A Leroyer

Subjects
Gastroenterology, General Medicine
Abstract

Background Anti-TNFs antibodies are the first biologic treatment option in inflammatory bowel disease (IBD). The long-term effectiveness of this strategy at the population level is poorly known, particularly in pediatric-onset IBD. Methods All patients diagnosed with Crohn’s disease (CD) or ulcerative colitis (UC) before the age of 17 between 1988 and 2011 in a population-based registry were followed retrospectively until 2013. Among patients treated with anti-TNFs, the cumulative probabilities of anti-TNF failure defined by primary failure, loss of response or intolerance were evaluated. Factors associated with anti-TNF failure were investigated by a Cox model. Results Among a total of 1007 patients with CD (median disease duration, 3.2 years IQR (1.2–7.6) and median follow-up 8.8 years (IQR, 4.6–14.2)) and 337 patients with UC (median disease duration, 2.5 years IQR [1.1–4.5] and median follow-up 7.2 years (IQR, 3.8–13.0)), respectively 481 (48%) and 81 (24%) were treated with anti-TNFs. Median age at anti-TNF initiation was 17.4 years (IQR, 15.1–20.9). Median duration of anti-TNF therapy was 20.4 months (IQR, 6.0–59.9). In CD, the probability of failure of 1st line anti-TNF therapy at 1, 3 and 5 years was respectively 29.3%, 47.0% and 54.6% for infliximab (n = 397) and 22.6%, 37.7% and 48.0% for adalimumab (n = 83). In UC, the probability of failure of 1st line anti-TNF therapy at 1, 3 and 5 years was respectively 37.3%, 49.0% and 61.0% for infliximab (n = 71) and 12.5% for these 3 timepoints for adalimumab (n = 10). In CD, probabilities of primary failure, loss of response and intolerance at 5 years were 10.4%, 36.7% and 6.8% (n = 480), respectively; in UC, these same probabilities were 7.5%, 39.2% and 11.3% (n = 81), respectively. Female sex (Hazard Ratio (HR) 1.43, 95% CI 1.09–1.87; p = 0.010) and intestinal resection prior anti-TNF initiation (HR 1.73, 95% CI 1.21–2.47, p = 0.003) were associated with anti-TNF failure in multivariate analysis. Conclusion In a population-based study of pediatric-onset IBD, approximately half of anti-TNFs users discontinue use within 5 years. Loss of response account for around two-thirds of failure, both for CD and UC.

Published
2022
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21. Dramatic Increase in Incidence of Ulcerative Colitis and Crohn's Disease (1988–2011): A Population-Based Study of French Adolescents

Author

Silvia Ghione, Hélène Sarter, Mathurin Fumery, Laura Armengol-Debeir, Guillaume Savoye, Delphine Ley, Claire Spyckerelle, Benjamin Pariente, Laurent Peyrin-Biroulet, Dominique Turck, Corinne Gower-Rousseau, J M Andre, M Antonietti, A Aouakli, A Armand, I Aroichane, F Assi, J P Aubet, E Auxenfants, F Ayafi-Ramelot, D Bankovski, B Barbry, N Bardoux, P Baron, A Baudet, B Bazin, A Bebahani, J P Becqwort, V Benet, H Benali, C Benguigui, Ben E Soussan, A Bental, I Berkelmans, J Bernet, K Bernou, C Bernou-Dron, P Bertot, N Bertiaux-Vandaële, V Bertrand, E Billoud, N Biron, B Bismuth, M Bleuet, F Blondel, V Blondin, P Bohon, E Boniface, P Bonnière, E Bonvarlet, P Bonvarlet, A Boruchowicz, R Bostvironnois, M Boualit, B Bouche, C Boudaillez, C Bourgeaux, M Bourgeois, A Bourguet, A Bourienne, J Branche, G Bray, F Brazier, P Breban, H Brihier, V Brung-Lefebvre, P Bulois, P Burgiere, J Butel, J Y Canva, V Canva-Delcambre, J P Capron, F Cardot, P Carpentier, E Cartier, J F Cassar, M Cassagnou, J F Castex, P Catala, S Cattan, S Catteau, B Caujolle, G Cayron, C Chandelier, M Chantre, J Charles, T Charneau, M Chavance-Thelu, D Chirita, A Choteau, J F Claerbout, P Y Clergue, H Coevoet, G Cohen, R Collet, J F Colombel, S Coopman, J Corvisart, A Cortot, F Couttenier, J F Crinquette, V Crombe, I Dadamessi, V Dapvril, T Davion, S Dautreme, J Debas, N Degrave, F Dehont, C Delatre, R Delcenserie, O Delette, T Delgrange, L Delhoustal, J S Delmotte, S Demmane, G Deregnaucourt, P Descombes, J P Desechalliers, P Desmet, P Desreumaux, G Desseaux, P Desurmont, A Devienne, E Devouge, M Devred, A Devroux, A Dewailly, S Dharancy, A Di Fiore, D Djeddi, R Djedir, M L Dreher-Duwat, R Dubois, C Dubuque, P Ducatillon, J Duclay, B Ducrocq, F Ducrot, P Ducrotte, A Dufilho, C Duhamel, D Dujardin, C Dumant-Forest, J L Dupas, F Dupont, Y Duranton, A Duriez, K El Achkar, M El Farisi, C Elie, M C Elie-Legrand, A Elkhaki, M Eoche, D Evrard, J P Evrard, A Fatome, B Filoche, L Finet, M Flahaut, C Flamme, D Foissey, P Fournier, M C Foutrein-Comes, P Foutrein, D Fremond, T Frere, M Fumery, P Gallet, C Gamblin, P S Ganga-Zandzou, R Gérard, G Geslin, Y Gheyssens, N Ghossini, S Ghrib, T Gilbert, B Gillet, D Godard, P Godard, J M Godchaux, R Godchaux, G Goegebeur, O Goria, F Gottrand, P Gower, B Grandmaison, M Groux, C Guedon, J F Guillard, L Guillem, F Guillemot, D Guimber, B Haddouche, S Hakim, D Hanon, V Hautefeuille, P Heckestweiller, G Hecquet, J P Hedde, H Hellal, P E Henneresse, B Heyman, M Heraud, S Herve, P Hochain, L Houssin-Bailly, P Houcke, B Huguenin, S Iobagiu, A Ivanovic, I Iwanicki-Caron, E Janicki, M Jarry, J Jeu, J P Joly, C Jonas, F Katherin, A Kerleveo, A Khachfe, A Kiriakos, J Kiriakos, O Klein, M Kohut, R Kornhauser, D Koutsomanis, J E Laberenne, G Laffineur, M Lagarde, P Lannoy, J Lapchin, M Lapprand, D Laude, R Leblanc, P Lecieux, N Leclerc, C Le Couteulx, J Ledent, J Lefebvre, P Lefiliatre, C Legrand, A Le Grix, P Lelong, B Leluyer, C Lenaerts, L Lepileur, A Leplat, E Lepoutre-Dujardin, H Leroi, M Y Leroy, J P Lesage, X Lesage, J Lesage, I Lescanne-Darchis, J Lescut, D Lescut, B Leurent, P Levy, M Lhermie, A Lion, B Lisambert, F Loire, S Louf, A Louvet, M Luciani, D Lucidarme, J Lugand, O Macaigne, D Maetz, D Maillard, H Mancheron, O Manolache, A B Marks-Brunel, R Marti, F Martin, G Martin, E Marzloff, P Mathurin, J Mauillon, V Maunoury, J L Maupas, B Mesnard, P Metayer, L Methari, B Meurisse, F Meurisse, L Michaud, X Mirmaran, P Modaine, A Monthe, L Morel, P E Mortier, E Moulin, O Mouterde, J Mudry, M Nachury, N'Guyen E Khac, B Notteghem, V Ollevier, A Ostyn, A Ouraghi, D Ouvry, B Paillot, N Panien-Claudot, C Paoletti, A Papazian, B Parent, B Pariente, J C Paris, P Patrier, L Paupart, B Pauwels, M Pauwels, R Petit, M Piat, S Piotte, C Plane, B Plouvier, E Pollet, P Pommelet, D Pop, C Pordes, G Pouchain, P Prades, A Prevost, J C Prevost, B Quesnel, A M Queuniet, J F Quinton, A Rabache, P Rabelle, G Raclot, S Ratajczyk, D Rault, V Razemon, N Reix, M Revillon, C Richez, P Robinson, J Rodriguez, J Roger, J M Roux, A Rudelli, A Saber, G Savoye, P Schlosseberg, M Segrestin, D Seguy, M Serin, A Seryer, F Sevenet, N Shekh, J Silvie, V Simon, C Spyckerelle, N Talbodec, A Techy, J L Thelu, A Thevenin, H Thiebault, J Thomas, J M Thorel, G Tielman, M Tode, J Toisin, J Tonnel, J Y Touchais, Y Touze, J L Tranvouez, C Triplet, D Turck, S Uhlen, E Vaillant, C Valmage, D Vanco, H Vandamme, E Vanderbecq, Vander E Eecken, P Vandermolen, P Vandevenne, L Vandeville, A Vandewalle, C Vandewalle, P Vaneslander, J P Vanhoove, A Vanrenterghem, P Varlet, I Vasies, G Verbiese, G Vernier-Massouille, P Vermelle, C Verne, P Vezilier-Cocq, B Vigneron, M Vincendet, J Viot, Y M Voiment, A Wacrenier, L Waeghemaecker, J Y Wallez, M Wantiez, F Wartel, J Weber, J L Willocquet, N Wizla, E Wolschies, A Zalar, B Zaouri, A Zellweger, C Ziade, Hôpital Jeanne de Flandre [Lille], Lille Inflammation Research International Center - U 995 (LIRIC), Institut Pasteur de Lille, Réseau International des Instituts Pasteur (RIIP)-Réseau International des Instituts Pasteur (RIIP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lille-Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille), Service d'Epidémiologie et de Santé Publique [Lille], Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille), Registre EPIMAD, CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-CHU Amiens-Picardie-Centre Hospitalier Régional Universitaire [Lille] (CHRU Lille), Service d'Hépato Gastroenterologie [CHU Amiens-Picardie], CHU Amiens-Picardie, Service d'Hépato-Gastroentérologie [CHU Rouen], Hôpital Charles Nicolle [Rouen]-CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Nutrition, inflammation et dysfonctionnement de l'axe intestin-cerveau (ADEN), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institute for Research and Innovation in Biomedicine (IRIB), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), UNIROUEN - UFR Santé (UNIROUEN UFR Santé), Normandie Université (NU)-Normandie Université (NU), Unité Pédiatrique [Saint-Vincent de Paul Lille], Hôpital Saint-Vincent de Paul, Nutrition-Génétique et Exposition aux Risques Environnementaux (NGERE), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Lorraine (UL), Service d'Hépato-gastro-entérologie [CHRU Nancy], Centre Hospitalier Régional Universitaire de Nancy (CHRU Nancy), Hôpital Charles Nicolle [Rouen], Normandie Université (NU)-Normandie Université (NU)-CHU Rouen, and Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Male, medicine.medical_specialty, Adolescent, Population, MEDLINE, Disease, 03 medical and health sciences, 0302 clinical medicine, Crohn Disease, Internal medicine, medicine, Humans, Colitis, Child, education, ComputingMilieux_MISCELLANEOUS, Crohn's disease, education.field_of_study, Hepatology, business.industry, Incidence, Incidence (epidemiology), Gastroenterology, [SDV.MHEP.HEG]Life Sciences [q-bio]/Human health and pathology/Hépatology and Gastroenterology, Inflammatory Bowel Diseases, medicine.disease, Ulcerative colitis, digestive system diseases, 3. Good health, Population based study, 030220 oncology & carcinogenesis, Colitis, Ulcerative, Female, 030211 gastroenterology & hepatology, France, business
Abstract

Few data are available to describe the changes in incidence of pediatric-onset inflammatory bowel disease (IBD). The aim of this study was to describe changes in incidence and phenotypic presentation of pediatric-onset IBD in northern France during a 24-year period.Pediatric-onset IBD (17 years) was issued from a population-based IBD study in France between 1988 and 2011. Age groups and digestive location were defined according to the Paris classification.1,350 incident cases were recorded (8.3% of all IBD) including 990 Crohn's disease (CD), 326 ulcerative colitis (UC) and 34 IBD unclassified (IBDU). Median age at diagnosis was similar in CD (14.4 years (Q1=11.8-Q3=16.0)) and UC (14.0 years (11.0-16.0)) and did not change over time. There were significantly more males with CD (females/males=0.82) than UC (females/males=1.25) (P=0.0042). Median time between onset of symptoms and IBD diagnosis was consistently 3 months (1-6). Mean incidence was 4.4/10In this population-based study, CD and UC incidences increased dramatically in adolescents across a 24-year span, suggesting that one or more strong environmental factors may predispose this population to IBD.

Published
2018
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22. Synthesis of Air-Stable CdSe/ZnS Core–Shell Nanoplatelets with Tunable Emission Wavelength

Author

Ali Hossain Khan, Zhiya Dang, Guillaume H. V. Bertrand, J. L. Movilla, Rosaria Brescia, Anatolii Polovitsyn, Iwan Moreels, and Beatriz Martín-García

Subjects
Photoluminescence, Materials science, METAL SULFIDE NANOPARTICLES, General Chemical Engineering, Exciton, Shell (structure), Nanotechnology, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, symbols.namesake, AMPLIFIED SPONTANEOUS EMISSION, Materials Chemistry, Absorption (electromagnetic radiation), PRECURSORS, Auger effect, business.industry, Heterojunction, CdSe/ZnS Core–Shell Nanoplatelets, General Chemistry, 021001 nanoscience & nanotechnology, AUGER RECOMBINATION, 0104 chemical sciences, Chemistry, ELECTRONIC-STRUCTURE, NANOCRYSTALS, LIGHT, Physics and Astronomy, Nanocrystal, symbols, Optoelectronics, photoluminescence, COLLOIDAL NANOPLATELETS, Quantum efficiency, SEMICONDUCTOR QUANTUM DOTS, ENERGY-TRANSFER, 0210 nano-technology, business
Abstract

In the past few years, several protocols have been reported on the synthesis of CdSe nanoplatelets with narrow photoluminescence (PL) spectrum, high PL quantum efficiency, and short exciton lifetime. The corresponding core/shell nanoplatelets are however still mostly based on CdSe/CdS, which possess an extended lifetime and a strong red shift of the band-edge absorption and emission, in accordance with a quasi-type-II band alignment. Here we report on a robust synthesis procedure to grow a ZnS shell around CdSe nanoplatelets at moderate temperatures of 100–150 °C, to improve the optical properties of CdSe nanoplatelets via a type-I core/shell heterostructure. The shell growth is performed under ambient atmosphere, in either toluene or 1,2-dichlorobenzene. The variation of the shell thickness induces a continuous red shift of the PL peak, eventually reaching 611 nm. The PL quantum efficiency is increased compared to the original CdSe cores, with values up to 60% depending on the shell thickness. High-resolution transmission electron microscopy reveals a bending of the nanoplatelets caused by strain due to 12% lattice mismatch between CdSe and ZnS. The present procedure can easily be translated to other core/shell nanocrystals, such as CdSe/CdS and CdSe/CdZnS nanoplatelets. The present publication is realized with the support of the Ministero degli Affari Esteri e della Cooperazione Internazionale (IONX-NC4SOL). This project has also received funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 696656 (GrapheneCore1). J.L.M. acknowledges support from UJI project P1-1B2014-24 and MINECO project CTQ2014-60178-P.

Published
2017
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24. Tuning trion binding energy and oscillator strength in a laterally finite 2D system: CdSe nanoplatelets as a model system for trion properties

Author

Alexander W. Achtstein, Nina Owschimikow, Mikhail Artemyev, Guillaume H. V. Bertrand, Sihem Jaziri, Ulrike Woggon, Iwan Moreels, Michael T. Quick, Sabrine Ayari, and Sotirios Christodoulou

Subjects
NEGATIVELY CHARGED EXCITONS, DYNAMICS, Technology and Engineering, Materials science, ZINCBLENDE CDSE, Oscillator strength, Exciton, Binding energy, 02 engineering and technology, SEMICONDUCTORS, 7. Clean energy, 01 natural sciences, Molecular physics, Condensed Matter::Materials Science, 0103 physical sciences, COHERENCE, General Materials Science, 010306 general physics, Condensed Matter::Quantum Gases, SPECTROSCOPY, Condensed Matter::Other, business.industry, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 021001 nanoscience & nanotechnology, LIFETIMES, 2-PHOTON ABSORPTION, Semiconductor, Physics and Astronomy, Quantum dot, COLLOIDAL NANOPLATELETS, Quantum efficiency, Trion, EMISSION, 0210 nano-technology, business, ddc:600, Lasing threshold
Abstract

We present a theoretical study combined with experimental validations demonstrating that CdSe nanoplatelets are a model system to investigate the tunability of trions and excitons in laterally finite 2D semiconductors. Our results show that the trion binding energy can be tuned from 36 meV to 18 meV with the lateral size and decreasing aspect ratio, while the oscillator strength ratio of trions to excitons decreases. In contrast to conventional quantum dots, the trion oscillator strength in a nanoplatelet at low temperature is smaller than that of the exciton. The trion and exciton Bohr radii become lateral size tunable,e.g.from similar to 3.5 to 4.8 nm for the trion. We show that dielectric screening has strong impact on these properties. By theoretical modeling of transition energies, binding energies and oscillator strength of trions and excitons and comparison with experimental findings, we demonstrate that these properties are lateral size and aspect ratio tunable and can be engineered by dielectric confinement, allowing to suppresse.g.detrimental trion emission in devices. Our results strongly impact further in-depth studies, as the demonstrated lateral size tunable trion and exciton manifold is expected to influence properties like gain mechanisms, lasing, quantum efficiency and transport even at room temperature due to the high and tunable trion binding energies.

Published
2020
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25. CdSe/CdS/CdTe Core/Barrier/Crown Nanoplatelets: Synthesis, Optoelectronic Properties, and Multiphoton Fluorescence Upconversion

Author

Iwan Moreels, Ayelet Teitelboim, Josep Planelles, Ali Hossain Khan, Chandra Sekhar M, Anatolii Polovitsyn, Guillaume H. V. Bertrand, Juan I. Climente, Dan Oron, Rosaria Brescia, and The present publication is realized with the support of the Ministero degli Affari Esteri e della Cooperazione Internazionale and the Ministry of Science, Technology and Space of the state of Israel (IONX-NC4SOL), and by the Crown Photonics Center of the Weizmann Institute of Science. This project has also received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement no. 714876 PHOCONA). J.C. and J.P. acknowledge the support from MINECO (project CTQ2017-83781-P) and UJI (project B2017-59). We also acknowledge the TEM facility of the Nematology Research Unit, member of the UGent TEM-Expertise center (life sciences).

Subjects
Photoluminescence, Exciton, General Physics and Astronomy, Physics::Optics, 02 engineering and technology, fluorescence upconversion, 010402 general chemistry, 01 natural sciences, Article, Condensed Matter::Materials Science, ternary architecture, General Materials Science, Quantum tunnelling, business.industry, Condensed Matter::Other, nanoplatelets, General Engineering, Heterojunction, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Cadmium telluride photovoltaics, Photon upconversion, k·p calculations, 0104 chemical sciences, Semiconductor, Nanocrystal, Optoelectronics, photoluminescence, 0210 nano-technology, business
Abstract

Colloidal two-dimensional (2D) nanoplatelet heterostructures are particularly interesting as they combine strong confinement of excitons in 2D materials with a wide range of possible semiconductor junctions due to a template-free, solution-based growth. Here, we present the synthesis of a ternary 2D architecture consisting of a core of CdSe, laterally encapsulated by a type-I barrier of CdS, and finally a type-II outer layer of CdTe as so-called crown. The CdS acts as a tunneling barrier between CdSe- and CdTe-localized hole states, and through strain at the CdS/CdTe interface, it can induce a shallow electron barrier for CdTe-localized electrons as well. Consequently, next to an extended fluorescence lifetime, the barrier also yields emission from CdSe and CdTe direct transitions. The core/barrier/crown configuration further enables two-photon fluorescence upconversion and, due to a high nonlinear absorption cross section, even allows to upconvert three near-infrared photons into a single green photon. These results demonstrate the capability of 2D heterostructured nanoplatelets to combine weak and strong confinement regimes to engineer their optoelectronic properties.

Published
2020

26. The role of the secondary fluorophore in ternary plastic scintillators aiming at discriminating fast neutrons from gamma-rays

Author

Matthieu Hamel, Romuald Woo, Guillaume H. V. Bertrand, Robert Bernard Pansu, Chrystele Dehe-Pittance, Zhengyu Zhang, Amélie Grabowski, Eva Montbarbon, Dominique Tromson, Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), 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'Intégration des Systèmes et des Technologies (LIST), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), ANR-15-CE39-0006,NESSYNED,Nouveaux Systèmes Scintillants pour la Détection de Neutrons(2015), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), and 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'Intégration des Systèmes et des Technologies (LIST (CEA))

Subjects
Materials science, Fluorophore, Physics::Instrumentation and Detectors, Biophysics, 02 engineering and technology, Scintillator, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 010402 general chemistry, 01 natural sciences, Biochemistry, neutron detection, chemistry.chemical_compound, Optics, Neutron detection, Figure of merit, Plastic scintillators, Triplet-triplet annihilation, Neutron, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], nuclear instrumentation, neutron-gamma discrimination, business.industry, Attenuation length, Gamma ray, Self-absorption, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Neutron temperature, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry, Secondary fluorophore, 0210 nano-technology, business
Abstract

International audience; Since Helium-3 shortage announcement, organic scintillators play a major role in neutron detection. Our laboratory decided to focus on plastic scintillators and their ability to discriminate fast neutrons from gamma rays. In this work, we highlight the influence of the secondary fluorophore in lab-made plastic scintillators. The secondary fluorophore is generally added in the scintillating mixture to shift the emission wavelength towards the transparency domain of the material to improve its attenuation length. Thus, it is considered as a harmless molecule and is barely seen as a key criterion that could enhance the performances of the organic scintillator. In our work, we demonstrate that this molecule, even added at a small concentration (typically in the range 0.02–0.2 wt%), directly impacts the neutron/gamma discrimination ability of plastics. Not only the secondary fluorophore plays a role in self-absorption of the scintillating material, but also the couple it creates with the primary fluorophore has to be carefully chosen, as some specific triplet energy transfers between the two fluorophores can influence the neutron/gamma discrimination abilities of the plastic scintillator. Aside from classical photophysical inconveniences such as self-absorption or diffusion, the possibility that the whole, bulk material was heterogeneous in a photochemical point of view was also checked. Thus, various samples were cut from bulk monoliths and their pulse shape discrimination compared with the parent scintillator in terms of Figure of Merit and light output.

Published
2019
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27. Size-dependent exciton substructure in CdSe nanoplatelets and its relation to photoluminescence dynamics

Author

Alexander W. Achtstein, Nina Owschimikow, Guillaume H. V. Bertrand, Riccardo Scott, Mikhail Artemyev, Marta Corona Castro, Iwan Moreels, Artsiom Antanovich, Judith F. Specht, Sotirios Christodoulou, Ulrike Woggon, Anatol Prudnikau, Marten Richter, and Laurens D. A. Siebbeles

Subjects
Photoluminescence, Exciton, RELAXATION, 02 engineering and technology, Electronic structure, QUANTUM DOTS, 010402 general chemistry, 01 natural sciences, Molecular physics, SEMICONDUCTORS, Condensed Matter::Materials Science, General Materials Science, Wave function, Quantum well, Condensed Matter::Other, LOCALIZATION, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 0104 chemical sciences, Chemistry, ELECTRONIC-STRUCTURE, NANOCRYSTALS, Physics and Astronomy, Quantum dot, Excited state, Substructure, COLLOIDAL NANOPLATELETS, RECOMBINATION DYNAMICS, 0210 nano-technology, EMISSION, ddc:600, FINE-STRUCTURE
Abstract

CdSe nanoplatelets can be synthesized with different lateral sizes; very small nanoplatelets have almost quantum dot like features (almost discrete exciton states), while very large ones are expected to have properties of colloidal quantum wells (exciton continuum). However, nanoplatelets can be in an intermediate confinement regime with a rich substructure of excitons, which is neither quantum dot like nor an ideal 2D exciton. In this manuscript, we discuss the experimental transition energies and relaxation dynamics of exciton states in CdSe platelets with varying lateral dimensions and compare them with a microscopic theoretical model including exciton-phonon scattering. The model takes special care of the interplay of confinement and Coulomb coupling in the intermediate regime showing strong changes with respect to simple weak or strong confinement models by solving the full four dimensional lateral factorization free exciton wavefunction. Depending on the platelet size broad resonances previously attributed to just ground and excited states are actually composed of a rich substructure of several exciton states in their temporal dynamics. We show that these factorization free exciton states can explain the spectral features observed in photoluminescence experiments. Furthermore we demonstrate that the interplay of exciton bright and dark states provides principle insights into the overall temporal relaxation dynamics, and allows tuning of the exciton cooling via lateral platelet size. Our results and theoretical approach are directly relevant for understanding e.g. the size tuneability of lasing, excitonic cooling dynamics or light harvesting applications in these and similar 2D systems of finite lateral size.

Published
2019
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28. Tuning the decay time of plastic scintillators

Author

Guillaume H. V. Bertrand, Hana Burešová, Malik Soumaré, Matthieu Hamel, Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), 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'Intégration des Systèmes et des Technologies (LIST (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Nuvia a.s., Laboratoire d'Intégration des Systèmes et des Technologies (LIST), and 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'Intégration des Systèmes et des Technologies (LIST)

Subjects
Materials science, Field (physics), Physics::Instrumentation and Detectors, General Chemical Engineering, Stacking, Time-correlated single photon counting, 02 engineering and technology, Scintillator, 010402 general chemistry, 01 natural sciences, Particle detector, materials, Optics, [CHIM]Chemical Sciences, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Decay time, nuclear instrumentation, Plastic scintillator, instrumentation, Range (particle radiation), Scintillation, detector, business.industry, primary fluorophore, Process Chemistry and Technology, Detector, 021001 nanoscience & nanotechnology, 0104 chemical sciences, 0210 nano-technology, business
Abstract

International audience; In the field of nuclear physics, plastic scintillators are popular and efficient radiation detectors thanks to the following properties: they can be prepared in large volumes, are cheap and various configurations can be afforded to the material. However, peculiar applications might require plastic scintillator with unusual scintillation decay times, such as laser beam positioning or detectors stacking. In the case of the scintillation decay time, commercial suppliers do not propose many choices, as only the range 0.7–10 ns is usually covered, along with a longer decay time – 285 ns – material. Herein we propose a new concept and associated formulations where the scintillation decay time can be finely chosen and tuned in a range starting at 2.5 ns and finishing around 90 ns. These materials are presented, synthesized and characterized.

Published
2019
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29. Tumeurs desmoïdes dans le cadre d’une polypose adénomateuse familiale chez une adolescente

Author

P. Afchain, Anne Munck, A. Bonnard, M. Creuzé, Jérôme Viala, and V. Bertrand

Subjects
0301 basic medicine, Gynecology, 03 medical and health sciences, medicine.medical_specialty, 0302 clinical medicine, business.industry, 030220 oncology & carcinogenesis, Pediatrics, Perinatology and Child Health, Medicine, 030105 genetics & heredity, business
Abstract

Resume Les tumeurs desmoides (TD) sont des tumeurs rares, infiltrant les tissus, denuees de potentiel metastatique. Elles sont le plus souvent sporadiques et dans 5 a 10 % des cas associees aux polyposes adenomateuses familiales (PAF). Elles apparaissent habituellement chez l’adulte jeune, plus rarement chez l’enfant. Nous rapportons le cas d’une adolescente de 14 ans qui avait subi une procto-colectomie totale en raison d’une PAF avec mutation de novo du gene APC, habituellement non associee aux TD. Trois ans plus tard, elle a presente des douleurs a la defecation. Le scanner a mis en evidence 2 TD intra-abdominales. Une exerese chirurgicale ayant ete ecartee en raison du risque de resection etendue du grele, un traitement par anti-estrogene et anti-inflammatoire non steroidien a ete instaure. Le scanner realise a 18 mois a montre une stabilisation des TD, mais l’adolescente gardait des douleurs chroniques difficiles a controler. Une surveillance radiologique reguliere a ete effectuee. Cette observation rappelle l’importance d’un depistage regulier des TD chez les sujets atteints de PAF, notamment apres une chirurgie, et ce quel que soit l’âge et le type de mutation. Des progres restent a faire pour determiner les facteurs de risque d’apparition d’une TD chez ces sujets et pour les traiter efficacement. La prise en charge therapeutique actuelle reste difficile du fait du caractere infiltrant et recidivant de ces tumeurs et necessite un avis pluridisciplinaire.

Published
2016
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30. Severe acute pancreatitis in a child with phenylketonuria

Author

V. Bertrand, H. Bruel, E. Smokvina, E. Masson, Groupe Hospitalier du Havre, ECLA, Génétique, génomique fonctionnelle et biotechnologies (UMR 1078) (GGB), Institut Brestois Santé Agro Matière (IBSAM), Université de Brest (UBO)-Université de Brest (UBO)-EFS-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut Brestois Santé Agro Matière (IBSAM), and Université de Brest (UBO)-Université de Brest (UBO)-EFS-Institut National de la Santé et de la Recherche Médicale (INSERM)

Subjects
Male, medicine.medical_specialty, [SDV]Life Sciences [q-bio], Computed tomography, Gastroenterology, Enteral administration, 03 medical and health sciences, 0302 clinical medicine, 030225 pediatrics, Internal medicine, Phenylketonurias, Back pain, medicine, Humans, Decompensation, Metabolic disease, Phenylalanine level, medicine.diagnostic_test, business.industry, medicine.disease, 3. Good health, Pancreatitis, Child, Preschool, Pediatrics, Perinatology and Child Health, Acute Disease, Acute pancreatitis, medicine.symptom, business
Abstract

We report for the first time severe acute pancreatitis in a child treated for phenylketonuria (PKU) discovered on neonatal screening. This 2-year-old boy was first hospitalized for bilious vomiting and moderate back pain. Laboratory values included a lipase level of 1.142 U/L, a phenylalanine level of 10mg/dL, and computed tomography revealed Balthazar grade E pancreatitis. Continuous enteral feeding was started on the 3rd day after admission. We observed clinical and biological improvement. Etiologic investigations for pancreatitis returned negative. Despite the severity of the pancreatitis, we did not observe decompensation of the metabolic disease. Specific nutritional management was necessary.

Published
2019
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31. A comparative study demonstrates strong size tunability of carrier–phonon coupling in CdSe-based 2D and 0D nanocrystals

Author

Jörg K. N. Lindner, Artsiom Antanovich, Guillaume H. V. Bertrand, Riccardo Scott, Anatol Prudnikau, Nina Owschimikow, Sotirios Christodoulou, Zeger Hens, Thomas Riedl, Iwan Moreels, Ulrike Woggon, Mikhail Artemyev, and Alexander W. Achtstein

Subjects
LINEWIDTH, Phonon, Dephasing, Exciton, Nanoparticle, 02 engineering and technology, QUANTUM DOTS, 010402 general chemistry, 01 natural sciences, Photonic metamaterial, Condensed Matter::Materials Science, General Materials Science, SPECTROSCOPY, Condensed matter physics, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 0104 chemical sciences, Multiple exciton generation, Coupling (electronics), Chemistry, 2-PHOTON ABSORPTION, TEMPERATURE-DEPENDENCE, Quantum dot, ddc:540, COLLOIDAL NANOPLATELETS, RECOMBINATION DYNAMICS, ELECTRON, 0210 nano-technology, EMISSION, ddc:600, FINE-STRUCTURE
Abstract

In a comparative study we investigate the carrier-phonon coupling in CdSe based core-only and hetero 2D as well as 0D nanoparticles. We demonstrate that the coupling can be strongly tuned by the lateral size of nanoplatelets, while, due to the weak lateral confinement, the transition energies are only altered by tens of meV. Our analysis shows that an increase in the lateral platelet area results in a strong decrease in the phonon coupling to acoustic modes due to deformation potential interaction, yielding an exciton deformation potential of 3.0 eV in line with theory. In contrast, coupling to optical modes tends to increase with the platelet area. This cannot be explained by Fröhlich interaction, which is generally dominant in II-VI materials. We compare CdSe/CdS nanoplatelets with their equivalent, spherical CdSe/CdS nanoparticles. Universally, in both systems the introduction of a CdS shell is shown to result in an increase of the average phonon coupling, mainly related to an increase of the coupling to acoustic modes, while the coupling to optical modes is reduced with increasing CdS layer thickness. The demonstrated size and CdS overgrowth tunability has strong implications for applications like tuning carrier cooling and carrier multiplication - relevant for solar energy harvesting applications. Other implications range from transport in nanosystems e.g. for field effect transistors or dephasing control. Our results open up a new toolbox for the design of photonic materials.

Published
2019

32. Arthroscopy-assisted Trillat procedure for anterior shoulder instability: Surgical technique and preliminary clinical results

Author

Pierre Martz, V. Bertrand, Emmanuel Baulot, Ludovic Labattut, Pierre Trouilloud, Marc Arcens, P.Y. Reybet Degat, Service orthopédie - traumatologie [CHU de Dijon], Centre Hospitalier Universitaire de Dijon - Hôpital François Mitterrand (CHU Dijon), Centre orthopédique [Dracy-Le-Fort], Université de Genève (UNIGE), Cognition, Action, et Plasticité Sensorimotrice [Dijon - U1093] (CAPS), and Université de Bourgogne (UB)-Institut National de la Santé et de la Recherche Médicale (INSERM)

Subjects
Adult, Joint Instability, Male, medicine.medical_specialty, Shoulder, Shoulder surgery, Adolescent, medicine.medical_treatment, [SDV.MHEP.CHI]Life Sciences [q-bio]/Human health and pathology/Surgery, 03 medical and health sciences, Arthroscopy, Young Adult, 0302 clinical medicine, Recurrence, Performed Procedure, Medicine, Humans, Orthopedics and Sports Medicine, Range of Motion, Articular, 030222 orthopedics, medicine.diagnostic_test, business.industry, Shoulder Joint, Open surgery, Shoulder arthroscopy, 030229 sport sciences, Anterior shoulder, Latarjet procedure, Surgery, Arthroscopic Trillat procedure, Patient Satisfaction, Operative time, Female, Anterior shoulder instability, business, Range of motion, [SDV.MHEP]Life Sciences [q-bio]/Human health and pathology, Follow-Up Studies
Abstract

International audience; The Trillat procedure performed as open surgery to treat anterior shoulder instability has been proven effective in preventing recurrences and restoring range of motion. An arthroscopically assisted variant of the Trillat procedure is described here, together with the preliminary clinical results in 18 patients treated between 2011 and 2014. After a mean follow-up of 24.7±9.8 months, the clinical outcomes were very satisfactory, with a Walch-Duplay score of 81.5±18.0, a Rowe score of 83.6±16.0, and 94% of satisfied or very satisfied patients. Mean operative time was 55±13min. No recurrences were recorded. As an easily performed procedure that provides good clinical outcomes, the arthroscopically assisted Trillat procedure is a simple and reproducible alternative to arthroscopic Latarjet procedure, which is still reserved for highly experienced surgical teams.

Published
2018
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33. Multifocal pelvic osteomyelitis in a child associated with cat-scratch disease: a case report and review of the literature

Author

E Smokvina, V Bertrand, E Benard, A Belgaid, K Zellali, and F Labbé

Subjects
Adult, DNA, Bacterial, Male, medicine.medical_specialty, Adolescent, medicine.drug_class, Antibiotics, Polymerase Chain Reaction, law.invention, Bone Infection, 03 medical and health sciences, Young Adult, 0302 clinical medicine, Pharmacotherapy, law, 030225 pediatrics, Medicine, Animals, Humans, 030212 general & internal medicine, Child, Pelvic Bones, Lymph node, Polymerase chain reaction, Bartonella henselae, biology, business.industry, Osteomyelitis, Cat-Scratch Disease, Cat-scratch disease, Middle Aged, biology.organism_classification, medicine.disease, Dermatology, Anti-Bacterial Agents, medicine.anatomical_structure, Treatment Outcome, Child, Preschool, Pediatrics, Perinatology and Child Health, Cats, Female, Lymph Nodes, business
Abstract

Bone infections in cat-scratch disease (CSD) are uncommon and the diagnosis can be missed. A 3-year-old boy with multifocal pelvic osteomyelitis caused by Bartonella henselae is reported. Serological tests were negative but DNA was detected by polymerase chain reaction assay of a lymph node. A swift recovery followed antibiotic treatment and there was completeresolution within a few months. The literature on 64 cases of osteomyelitis owing to CSD in children and adults since 1954 is reviewed.

Published
2018

34. PRO93 DEMOGRAPHICS AND TREATMENT PATTERNS FOR CHARCOT-MARIE-TOOTH DISEASE IN THE EU AND US: INTERIM RESULTS FROM AN INTERNATIONAL DIGITAL REAL-WORLD STUDY

Author

V. Bertrand, X. Paoli, F.P. Thomas, S. Attarian, A. Gray, M. Larkin, M. Larrazet, H. Kousoulakou, T. Ziemssen, E. Bagshaw, C. Hollett, A. Moore, K. Monteiro, T. Sevilla, and Y. Boutalbi

Subjects
medicine.medical_specialty, Tooth disease, Demographics, business.industry, Health Policy, Family medicine, Interim, Public Health, Environmental and Occupational Health, medicine, business
Published
2019
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35. PRO138 PRODUCTIVITY LOSSES IN PEOPLE WITH CHARCOT-MARIE-TOOTH DISEASE IN THE EU AND US: INTERIM RESULTS FROM AN INTERNATIONAL DIGITAL REAL-WORLD EVIDENCE STUDY

Author

M. Larrazet, A. Moore, X. Paoli, S. Llewellyn, E. Bagshaw, K. Monteiro, T. Ziemssen, F.P. Thomas, H. Kousoulakou, M. Larkin, S. Attarian, V. Bertrand, Y. Boutalbi, C. Hollett, A. Gray, and T. Sevilla

Subjects
Tooth disease, Health Policy, Interim, Development economics, Public Health, Environmental and Occupational Health, Economics, Real world evidence, Productivity
Published
2019
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36. Gadolinium for neutron detection in current nuclear instrumentation research: A review

Author

Q. Lecomte, Matthieu Hamel, Romain Coulon, Jonathan Dumazert, Guillaume H. V. Bertrand, Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), 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'Intégration des Systèmes et des Technologies (LIST), 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'Intégration des Systèmes et des Technologies (LIST (CEA)), and 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'Intégration des Systèmes et des Technologies (LIST (CEA))

Subjects
Nuclear and High Energy Physics, EFFICIENCY, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Gadolinium, Nuclear engineering, Astrophysics::High Energy Astrophysical Phenomena, Neutron poison, chemistry.chemical_element, 02 engineering and technology, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], plastic scintillator, 01 natural sciences, 7. Clean energy, THERMAL-NEUTRONS, Nuclear physics, LOADED PLASTIC SCINTILLATORS, 0103 physical sciences, Neutron detection, Neutron, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Nuclear Experiment, Instrumentation, nuclear instrumentation, Physics, SPECTROSCOPY, Isotope, 010308 nuclear & particles physics, LIQUID SCINTILLATOR, Solid-state media, neutrons, Gamma ray, DOSIMETRY, GAMMA, 021001 nanoscience & nanotechnology, Neutron temperature, CAPTURE, Neutron capture, COMPENSATION, chemistry, Gas, radioactivity, Gamma-rays, ionizing radiation, 0210 nano-technology, DATA SHEETS, [CHIM.RADIO]Chemical Sciences/Radiochemistry
Abstract

Natural gadolinium displays a number of remarkable physical properties: it is a rare earth element, composed of seven stable or quasi-stable isotopes, with an exceptionally high magnetization and a Curie point near room temperature. Its use in the field of nuclear instrumentation historically relates to its efficiency as a neutron poison in power reactors. Gadolinium is indeed the naturally occurring element with the highest interaction probability with neutrons at thermal energy, shared between Gd-157 (15.65%, 254000 b cross section) and Gd-155 (14.8%, 60900 b) isotopes. Considering that neutron capture results in an isotopic change, followed by a radiative rearrangement of nuclear and atomic structures, Gd may be embodied not merely as a neutron poison but as a neutron converter into a prompt photon and an electron source term. Depending on the nature and energy of the reaction products (from a few-keV Auger electrons up to 8 MeV gamma rays) that the detector aims at isolating as an indirect neutron signature, a variety of sensor media and counting methods have been introduced during the last decades. This review first draws a theoretical description of the radiative cascade following Gd ( n , γ ) capture. The cascade may be subdivided into regions of interest, each corresponding to dedicated detection designs and optimizations whose current status is detailed. This inventory has allowed the authors to extract and benchmark key figures of merit for the definition of a detection scheme: neutron attenuation, neutron sensitivity (cps/nv), gamma rejection, neutron detection limit in a mixed field, intrinsic or extrinsic moderation, and transportability. On this basis, the authors have identified promising paths for Gd-based neutron detection in contemporary instrumentation.

Published
2018
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38. Aggregation and travel time calculation over large scale traffic networks: An empiric study on the Grenoble City

Author

B. Gouin, Giacomo Casadei, Carlos Canudas-de-Wit, V. Bertrand, Networked Controlled Systems (NECS), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Département Automatique (GIPSA-DA), Grenoble Images Parole Signal Automatique (GIPSA-lab ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Grenoble Images Parole Signal Automatique (GIPSA-lab ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), and European Project: 694209,Advanced Grant (AdG), ERC-2015-AdG ,Scale-FreeBack(2016)

Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other, Heading (navigation), Similarity (geometry), Computer science, Computation, [INFO.INFO-DS]Computer Science [cs]/Data Structures and Algorithms [cs.DS], Transportation, Scale (descriptive set theory), 010501 environmental sciences, 01 natural sciences, [SPI.GCIV.IT]Engineering Sciences [physics]/Civil Engineering/Infrastructures de transport, 11. Sustainability, 0502 economics and business, [MATH]Mathematics [math], Cluster analysis, large scale traffic networks, 0105 earth and related environmental sciences, Civil and Structural Engineering, 050210 logistics & transportation, 05 social sciences, Computer Science Applications, Travel time, travel time estimation, Automotive Engineering, Metric (mathematics), Graph (abstract data type), clustering and aggregation, Algorithm
Abstract

International audience; In this paper we consider aggregation technique to reduce the complexity of large-scale traffic network. In particular, we consider the city of Grenoble and show that, by clustering adjacent sections based on a similarity of speed condition, it is possible to cut down the complexity of the network without loosing crucial and intrinsic information. To this end, we consider travel time computation as a metric of comparison between the original graph and the reduced one: for each cluster we define four attributes (average speed, primary and secondary length and heading) and show that, in case of an aggregation rate of 95%, these attributes are sufficient in order to maintain the travel time error below the 25%.

Published
2018
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39. Large irradiation doses can improve the fast neutron/gamma discriminating capability of plastic scintillators

Author

Dominique Tromson, Sylvain Gaillard, Robert Pansu, Romuald Woo, Matthieu Hamel, Camille Frangville, Guillaume H. V. Bertrand, Jean-Luc Renaud, Eva Montbarbon, Marie-Noëlle Amiot, Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), 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'Intégration des Systèmes et des Technologies (LIST), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire National Henri Becquerel (LNHB), Laboratoire de chimie moléculaire et thioorganique (LCMT), Centre National de la Recherche Scientifique (CNRS)-Institut Normand de Chimie Moléculaire Médicinale et Macromoléculaire (INC3M), Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU), ANR-15-CE39-0006,NESSYNED,Nouveaux Systèmes Scintillants pour la Détection de Neutrons(2015), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), 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'Intégration des Systèmes et des Technologies (LIST (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Département d'instrumentation Numérique (DIN (CEA-LIST)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut Normand de Chimie Moléculaire Médicinale et Macromoléculaire (INC3M), Normandie Université (NU)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), and Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
HARDNESS, Materials science, General Physics and Astronomy, 02 engineering and technology, Scintillator, Radiation, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, plastic scintillator, Particle detector, CO-60, neutron/gamma discrimination, 0103 physical sciences, Radiation damage, Dosimetry, Figure of merit, WATER, Neutron, Irradiation, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Physical and Theoretical Chemistry, Radiation detection and measurement, nuclear instrumentation, instrumentation, neutron-gamma discrimination, STABILITY, 010308 nuclear & particles physics, Radiochemistry, neutrons, RAYS, DOSIMETRY, 021001 nanoscience & nanotechnology, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, RADIATION-DAMAGE, radioactivity, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Gamma-rays, ionizing radiation, 0210 nano-technology, large irradiation dose
Abstract

International audience; When new materials appear as potential alternatives for radiation detection, several criteria have to be fulfilled. The one presented herein is the response variation to large irradiation doses of neutron/gamma discriminating plastic scintillators. Thus, several samples were exposed to high gamma doses reaching 10 kGy. They were characterized in terms of gamma spectrometry and fast neutron/gamma discrimination, prior to and after irradiation. Results show an unexpected increase of the figure of merit (FoM), which is the numerical value for n/g discrimination performances. An in-depth investigation evaluates the physicochemical impact of such large doses within the material. The characterization includes photophysics, radiation/matter interaction and chemical analyses (EPR, 1H NMR, fluorescence spectroscopy and HRMS).

Published
2017
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40. Structural Variation of Carbazole Derivatives for Plastic Scintillation Applications

Author

Fabien Sguerra, Robert Pansu, Jean-Luc Renaud, Guillaume H. V. Bertrand, Eva Montbarbon, Matthieu Hamel, Sylvain Gaillard, Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut Parisien de Chimie Moléculaire (IPCM), Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie moléculaire et thioorganique (LCMT), Centre National de la Recherche Scientifique (CNRS)-Institut Normand de Chimie Moléculaire Médicinale et Macromoléculaire (INC3M), Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut Normand de Chimie Moléculaire Médicinale et Macromoléculaire (INC3M), Normandie Université (NU)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Le Havre Normandie (ULH), and Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
chemistry.chemical_classification, Scintillation, Fluorophore, Materials science, 010405 organic chemistry, Carbazole, Organic Chemistry, Radical polymerization, Context (language use), Polymer, Scintillator, 010402 general chemistry, Photochemistry, 01 natural sciences, 0104 chemical sciences, Analytical Chemistry, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, chemistry, Physical and Theoretical Chemistry, Luminescence, ComputingMilieux_MISCELLANEOUS
Abstract

We report the preparation of various plastic scintillators embedding the carbazole moiety. Thanks to advantageous luminescence properties and versatility, it is a candidate of choice for such applications. Based on various modifications of the carbazole pattern, it can play various roles: as the polymer matrix, as the primary or even as the secondary fluorophore. In this context, several examples are provided and commented. Embedded in the polymer matrix, PVK and poly(styrene-co-N-vinylcarbazole) were prepared by bulk radical polymerization. N-(2-ethylhexyl)carbazole (EHCz) is a particularly suited molecule which can act either as a primary fluorophore when used at low concentrations (eventually coupled with POPOP or bis-MSB as wavelength shifter), or as both primary and secondary fluorophore if the concentration inside the polymer matrix is elevated. The second option involves the emission of the excimer of the molecule. EHCz was compared with a cousin molecule, namely N-(ethyl)carbazole. Lastly, another carbazole-containing molecule (4CzIPN) was loaded in a polymer matrix as secondary fluorophore. Scintillation results show its efficiency to shift the scintillation response to wavelengths close to 500 nm. Thus, several new plastic scintillators were prepared, and their main photophysical properties given. The scintillation properties were also recorded and commented, which highlight the interest of carbazole derivatives as fluorophore in this area of nuclear detection.

Published
2017
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42. PRO37 HEALTHCARE RESOURCE USE IN CHARCOT-MARIE-TOOTH DISEASE IN THE EU AND US: INTERIM RESULTS FROM AN INTERNATIONAL DIGITAL REAL-WORLD STUDY

Author

T. Sevilla, Y. Boutalbi, H. Kousoulakou, T. Ziemssen, E. Bagshaw, V. Bertrand, C. Hollett, S. Attarian, M. Larkin, A. Moore, F.P. Thomas, X. Paoli, K. Monteiro, A. Gray, and M. Larrazet

Subjects
Tooth disease, business.industry, Health Policy, Political science, Interim, Health care, Public Health, Environmental and Occupational Health, medicine, Resource use, Medical emergency, business, medicine.disease
Published
2019
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43. Nanoparticles-loaded plastic scintillators for fast/thermal neutrons/gamma discrimination: Simulation and results

Author

Jonathan Dumazert, Guillaume H. V. Bertrand, Matthieu Hamel, Camille Frangville, Amélie Grabowski, Clément Lynde, Eva Montbarbon, Romain Coulon, Amélie Venerosy, Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), 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'Intégration des Systèmes et des Technologies (LIST), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire Capteurs Diamant (LCD-LIST), ANR-15-CE39-0006,NESSYNED,Nouveaux Systèmes Scintillants pour la Détection de Neutrons(2015), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), and 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'Intégration des Systèmes et des Technologies (LIST (CEA))

Subjects
Ionizing radiation, Nuclear and High Energy Physics, Analytical chemistry, Nanoparticle, chemistry.chemical_element, intrumentation, 02 engineering and technology, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Radiation, Scintillator, 01 natural sciences, 0103 physical sciences, MCNP, Figure of merit, fast neutrons, Neutron, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Instrumentation, nuclear instrumentation, thermal neutrons, Plastic scintillator, Physics, Neutron-gamma discrimination, nanoparticle-loaded scintillator, 010308 nuclear & particles physics, Gamma ray, simulation, 021001 nanoscience & nanotechnology, Neutron temperature, lithium tetraborate, detection chamber, chemistry, radioactivity, nanoparticles, Lithium, 0210 nano-technology
Abstract

We report herein the application of a new series of plastic scintillators loaded with lithium tetraborate nanoparticles (Li 2 B 4 O 7 ) designed for the simultaneous detection of fast neutrons, thermal neutrons and gamma-rays. First, MCNP simulations are performed to highlight the potential benefit of Li 2 B 4 O 7 loading. Then, a nanoparticle-loaded scintillator is prepared and evaluated towards the detection of a partially thermalized neutron/gamma 252-californium source. Several scenarios of radiation/matter interactions are evaluated against the observed results. A detection chamber composed of boron-containing chipboard wood has been specifically designed and a subtraction method was set up to afford the best discrimination pattern. For the first time, a triple discrimination is presented with a nanoparticles-loaded plastic scintillator, where both 6 Li(n, α ) and 10 B(n, α ) signatures are observed. A Figure of Merit of 1.40 was calculated between fast neutrons and gamma rays around 480 keVee. The Figure of Merit between fast + thermal neutrons and gamma rays is slightly worse as it is 1.16 at 380 keVee.

Published
2019
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44. PRO45 PATIENT-REPORTED REAL-WORLD TREATMENT PATTERNS FOR CHARCOT-MARIE-TOOTH DISEASE IN THE UK AND US ASSESSED USING A DIGITAL 'BRING YOUR OWN DEVICE PLATFORM'

Author

H. Kousoulakou, S. Attarian, V. Bertrand, M. Larkin, E. Bagshaw, A. Moore, X. Paoli, T. Ziemssen, D. Tanesse, F.P. Thomas, and Y. Boutalbi

Subjects
Tooth disease, business.industry, Health Policy, Public Health, Environmental and Occupational Health, Bring your own device, Medicine, Optometry, business
Published
2019
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46. Thiophene-based covalent organic frameworks

Author

Ta-Chung Ong, Guillaume H. V. Bertrand, Vladimir K. Michaelis, Robert G. Griffin, and Mircea Dincă

Subjects
chemistry.chemical_classification, Multidisciplinary, Materials science, Molecular Structure, Polymers, Extramural, Thiophenes, Polymer, Charge-transfer complex, Tetracyanoquinodimethane, Combinatorial chemistry, chemistry.chemical_compound, Monomer, chemistry, Covalent bond, Physical Sciences, Polymer chemistry, Thiophene, Molecule
Abstract

We report the synthesis and characterization of covalent organic frameworks (COFs) incorporating thiophene-based building blocks. We show that these are amenable to reticular synthesis, and that bent ditopic monomers, such as 2,5-thiophenediboronic acid, are defect-prone building blocks that are susceptible to synthetic variations during COF synthesis. The synthesis and characterization of an unusual charge transfer complex between thieno[3,2- b ]thiophene-2,5-diboronic acid and tetracyanoquinodimethane enabled by the unique COF architecture is also presented. Together, these results delineate important synthetic advances toward the implementation of COFs in electronic devices.

Published
2013
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47. Compensated bismuth-loaded plastic scintillators for neutron detection using low-energy pseudo-spectroscopy

Author

Romain Coulon, Guillaume H. V. Bertrand, Stephane Normand, Matthieu Hamel, Jonathan Dumazert, Laurence Méchin, Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), 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'Intégration des Systèmes et des Technologies (LIST), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Equipe Electronique - Laboratoire GREYC - UMR6072, Groupe de Recherche en Informatique, Image et Instrumentation de Caen (GREYC), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), 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'Intégration des Systèmes et des Technologies (LIST (CEA)), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), and Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear and High Energy Physics, Photon, spectrum analysis, Statistical fluctuations, Scintillator, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], plastic scintillator, 01 natural sciences, 030218 nuclear medicine & medical imaging, Compensation (engineering), spectrometry, 03 medical and health sciences, GADOLINIUM, 0302 clinical medicine, Optics, 0103 physical sciences, Thermal, Neutron detection, Neutron, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], signal processing, Instrumentation, nuclear instrumentation, Physics, Neutron-gamma discrimination, detector, 010308 nuclear & particles physics, business.industry, Modified plastic scintillators, neutrons, PULSE-SHAPE DISCRIMINATION, Neutron temperature, radioactivity, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, counting, ionizing radiation, business, Compensation, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing
Abstract

International audience; Gadolinium-covered modified plastic scintillators show a high potential for the deployment of cost-effective neutron detectors. Taking advantage of the low-energy photon and electron signature of thermal neutron captures in gadolinium-155 and gadolinium-157 however requires a background correction. In order to display a trustable rate, dual compensation schemes appear as an alternative to Pulse Shape Discrimination. This paper presents the application of such a compensation scheme to a two-bismuth loaded plastic scintillator system. A detection scintillator interacts with incident photon and fast neutron radiations and is covered with a gadolinium converter to become thermal neutron-sensitive as well. In the meantime, an identical compensation scintillator, covered with terbium, solely interacts with the photon and fast neutron part of incident radiations. After the acquisition and the treatment of the counting signals from both sensors, a hypothesis test determines whether the resulting count rate after subtraction falls into statistical fluctuations or provides a robust image of neutron activity. A laboratory prototype is tested under both photon and neutron radiations, allowing us to investigate the performance of the overall compensation system. The study reveals satisfactory results in terms of robustness to a cesium-137 background and in terms of sensitivity in presence of a californium-252 source.

Published
2016
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48. Gadolinium-loaded Plastic Scintillators for Thermal Neutron Detection using Compensation

Author

Fabien Sguerra, Stephane Normand, Jonathan Dumazert, Guillaume H. V. Bertrand, Matthieu Hamel, Romain Coulon, Frederick Carrel, Laurence Méchin, Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), 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'Intégration des Systèmes et des Technologies (LIST), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Equipe Electronique - Laboratoire GREYC - UMR6072, Groupe de Recherche en Informatique, Image et Instrumentation de Caen (GREYC), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), 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'Intégration des Systèmes et des Technologies (LIST (CEA)), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), and Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear and High Energy Physics, Materials science, 02 engineering and technology, Radiation, Scintillator, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], plastic scintillator, neutron detection, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Optics, Neutron detection, photons, Neutron, Compensation techniques, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], Electrical and Electronic Engineering, plastic scintillators, nuclear instrumentation, Bonner sphere, instrumentation, Neutron-gamma discrimination, detector, business.industry, Neutron stimulated emission computed tomography, neutrons, Neutron radiation, 021001 nanoscience & nanotechnology, Neutron temperature, Nuclear Energy and Engineering, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, 0210 nano-technology, business, ionizing radiation, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing
Abstract

International audience; Plastic scintillator loading with gadolinium-rich organometallic complexes shows a high potential for the deployment of efficient and cost-effective neutron detectors. Due to the low-energy photon and electron signature of thermal neutron capture by Gd-155 and Gd-157, alternative treatment to pulse-shape discrimination has to be proposed in order to display a count rate. This paper discloses the principle of a compensation method applied to a two-scintillator system: a detection scintillator interacts with photon and fast neutron radiation and is loaded with gadolinium organometallic compound to become a thermal neutron absorber, while a not-gadolinium loaded compensation scintillator solely interacts with the fast neutron and photon part of incident radiation. After the nonlinear smoothing of the counting signals, a hypothesis test determines whether the resulting count rate post-background response compensation falls into statistical fluctuations or provides a robust indication of neutron activity. Laboratory samples are tested under both photon and neutron irradiations, allowing the authors to investigate the performance of the overall detection system in terms of sensitivity and detection limits, especially with regards to a similar-active volume He-3 based commercial counter. The study reveals satisfactory figures of merit in terms of sensitivity and directs future investigation toward promising paths.

Published
2016
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49. N-(2-Ethylhexyl)carbazole: A New Fluorophore Highly Suitable as a Monomolecular Liquid Scintillator

Author

Romain Coulon, Robert Pansu, Élodie Magnier, Fabien Sguerra, Matthieu Hamel, Guillaume H. V. Bertrand, Eva Montbarbon, Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), 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'Intégration des Systèmes et des Technologies (LIST (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, French Direction Generale de l'ArmementSecretariat General de la Defense et de la Securite Nationale, ANR-12-SECU-0002,Lux plastic,Amélioration de la réponse de scintillateurs plastiques par luminescence de complexes organométalliques(2012), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), and 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'Intégration des Systèmes et des Technologies (LIST)

Subjects
Fluorophore, Physics::Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, Analytical chemistry, 02 engineering and technology, Scintillator, 010402 general chemistry, 01 natural sciences, Catalysis, chemistry.chemical_compound, radiochemistry, Scintillation, SOLVENT, scintillation, Chemistry, Carbazole, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Organic Chemistry, Gamma ray, GAMMA-RAYS, excimer, General Chemistry, 021001 nanoscience & nanotechnology, Fluorescence, Neutron temperature, 0104 chemical sciences, carbazoles, DISCRIMINATION, Scintillation counter, fluorescence, 0210 nano-technology, [CHIM.RADIO]Chemical Sciences/Radiochemistry
Abstract

International audience; The synthesis, photophysical properties, and applications in scintillation counting of N-(2-ethylhexyl)carbazole (EHCz) are reported. This molecule displays all of the required characteristics for an efficient liquid scintillator (emission wavelength, scintillation yield), and can be used without any extra fluorophores. Thus, its scintillation properties are discussed, as well as its fast neutron/gamma discrimination. For the latter application, the material is compared with the traditional liquid scintillator BC-501 A, and other liquid fluorescent molecules classically used as scintillation solvents, such as xylene, pseudocumene (PC), linear alkylbenzenes (LAB), diisopropylnaphthalene (DIN), 1-methylnaphthalene (1-MeNapht), and 4-isopropylbiphenyl (iPrBiph). For the first time, an excimeric form of a molecule has been advantageously used in scintillation counting. A moderate discrimination between fast neutrons and gamma rays was observed in bulk EHCz, with an apparent neutron/gamma discrimination potential half of that of BC-501 A.

Published
2016
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50. p-State Luminescence in CdSe Nanoplatelets: Role of Lateral Confinement and a Longitudinal Optical Phonon Bottleneck

Author

Iwan Moreels, Alexander W. Achtstein, Sebastian Kickhöfel, Guillaume H. V. Bertrand, Andrei Schliwa, Ulrike Woggon, Stefan T. Jagsch, Mikhail Artemyev, Anatol Prudnikau, Sotirios Christodoulou, Artsiom Antanovich, and Riccardo Scott

Subjects
education.field_of_study, Condensed matter physics, Phonon, Oscillator strength, Exciton, Population, General Physics and Astronomy, 02 engineering and technology, Rate equation, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Condensed Matter::Materials Science, Excited state, 0210 nano-technology, Ground state, education, Lasing threshold
Abstract

We evidence excited state emission from p states well below ground state saturation in CdSe nanoplatelets. Size-dependent exciton ground and excited state energies and population dynamics are determined by four independent methods: time-resolved PL, time-integrated PL, rate equation modeling, and Hartree renormalized k·p calculations-all in very good agreement. The ground state-excited state energy spacing strongly increases with the lateral platelet quantization. Depending on its detuning to the LO phonon energy, the PL decay of CdSe platelets is governed by a size tunable LO phonon bottleneck, related to the low exciton-phonon coupling, very large oscillator strength, and energy spacing of both states. This is, for instance, ideal to tune lasing properties. CdSe platelets are perfectly suited to control the exciton-phonon interaction by changing their lateral size while the optical transition energy is determined by their thickness.

Published
2016
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