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Journal articles on the topic 'Facteur g des excitons'

Author: Grafiati

Published: 24 June 2023

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1

Ju, Long, Lei Wang, Ting Cao, Takashi Taniguchi, Kenji Watanabe, Steven G. Louie, Farhan Rana, et al. "Tunable excitons in bilayer graphene." Science 358, no. 6365 (November 16, 2017): 907–10. http://dx.doi.org/10.1126/science.aam9175.

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Excitons, the bound states of an electron and a hole in a solid material, play a key role in the optical properties of insulators and semiconductors. Here, we report the observation of excitons in bilayer graphene (BLG) using photocurrent spectroscopy of high-quality BLG encapsulated in hexagonal boron nitride. We observed two prominent excitonic resonances with narrow line widths that are tunable from the mid-infrared to the terahertz range. These excitons obey optical selection rules distinct from those in conventional semiconductors and feature an electron pseudospin winding number of 2. An external magnetic field induces a large splitting of the valley excitons, corresponding to a g-factor of about 20. These findings open up opportunities to explore exciton physics with pseudospin texture in electrically tunable graphene systems.

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2

N. R. Senthil Kumar, N. R. Senthil Kumar, A. John Peter A. John Peter, and Chang Woo Lee Chang Woo Lee. "Optical properties of excitons in strained Gax In1-xAs/GaAs quantum dot: ef fect of geometrical conf inement on exciton g-factor." Chinese Optics Letters 11, no. 8 (2013): 082501–82507. http://dx.doi.org/10.3788/col201311.082501.

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3

Faria Junior, Paulo E., Klaus Zollner, Tomasz Woźniak, Marcin Kurpas, Martin Gmitra, and Jaroslav Fabian. "First-principles insights into the spin-valley physics of strained transition metal dichalcogenides monolayers." New Journal of Physics 24, no. 8 (August 1, 2022): 083004. http://dx.doi.org/10.1088/1367-2630/ac7e21.

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Abstract Transition metal dichalcogenides (TMDCs) are ideal candidates to explore the manifestation of spin-valley physics under external stimuli. In this study, we investigate the influence of strain on the spin and orbital angular momenta, effective g-factors, and Berry curvatures of several monolayer TMDCs (Mo and W based) using a full ab initio approach. At the K-valleys, we find a surprising decrease of the conduction band spin expectation value for compressive strain, consequently increasing the dipole strength of the dark exciton by more than one order of magnitude (for ∼ 1 % – 2 % strain variation). We also predict the behavior of direct excitons g-factors under strain: tensile (compressive) strain increases (decreases) the absolute value of g-factors. Strain variations of ∼1% modify the bright (A and B) excitons g-factors by ∼0.3 (0.2) for W (Mo) based compounds and the dark exciton g-factors by ∼0.5 (0.3) for W (Mo) compounds. Our predictions could be directly visualized in magneto-optical experiments in strained samples at low temperature. Additionally, our calculations strongly suggest that strain effects are one of the possible causes of g-factor fluctuations observed experimentally. By comparing the different TMDC compounds, we reveal the role of spin–orbit coupling (SOC): the stronger the SOC, the more sensitive are the spin-valley features under applied strain. Consequently, monolayer WSe2 is a formidable candidate to explore the role of strain on the spin-valley physics. We complete our analysis by considering the side valleys, Γ and Q points, and by investigating the influence of strain in the Berry curvature. In the broader context of valley- and strain-tronics, our study provides fundamental microscopic insights into the role of strain in the spin-valley physics of TMDCs, which are relevant to interpret experimental data in monolayer TMDCs as well as TMDC-based van der Waals heterostructures.

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4

Lalitha, D., A. John Peter, and Chang Woo Lee. "Magneto-trions in a GaMnAs/Ga0.6Al0.4As Quantum Dot." International Journal of Nanoscience 14, no. 05n06 (October 2015): 1550023. http://dx.doi.org/10.1142/s0219581x15500234.

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Magneto bound exciton and the charged exciton in a GaMn 0.02 As / Ga 0.6 Al 0.4 As quantum dot are reported with the spatial confinement effect. The numerical calculations are carried out with the inclusion of exchange interaction between the carrier and the magnetic impurities. The binding energies of exciton and the trions and the optical transition energy are obtained as a function of dot radius. Numerical computations are followed using exact diagonalization method. The spin polaronic energy of the exciton and the charged excitons are obtained using a mean field theory in the presence of magnetic field strength. The magnetization of Mn ion impurities as a function of dot radius is investigated. The effective g-factor of conduction (valence) band electron (hole) is obtained in the GaMnAs quantum dot. The magnetic field induced size dependence of effective Landé g-factor is computed. The result shows that (i) the geometrical dependence on sp-d exchange interaction in the GaMn 0.02 As / Ga 0.6 Al 0.4 As quantum dot has great influence with the geometrical confinement, (ii) the monotonic behavior of effective g-factor with the reduction of dot radius is observed, (iii) the Landé factor is more sensitive if the geometrical confinement effect is included and (iv) the value of effective g-factor increases when the spatial confinement is enhanced for all the dot radii. Our results show that the effective Landé g-factor can be manipulated negative to positive values in the GaMn 0.02 As / Ga 0.4 Al 0.6 As quantum dot.

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5

Corfdir, P., Y. Fontana, B. Van Hattem, E. Russo-Averchi, M. Heiss, A. Fontcuberta i Morral, and R. T. Phillips. "Tuning the g-factor of neutral and charged excitons confined to self-assembled (Al,Ga)As shell quantum dots." Applied Physics Letters 105, no. 22 (December 2014): 223111. http://dx.doi.org/10.1063/1.4903515.

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6

Song, Fei-Long, Yu-Nuan Wang, Feng Zhang, Shi-Yao Wu, Xin Xie, Jing-Nan Yang, Si-Bai Sun, et al. "The g-factor anisotropy of trapped excitons in CH₃NH₃PbBr₃ perovskite." Acta Physica Sinica 69, no. 16 (2020): 167102. http://dx.doi.org/10.7498/aps.69.20200646.

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7

Lacroix, Y., C. A. Tran, S. P. Watkins, and M. L. W. Thewalt. "Optical identification of the exciton–polariton in epitaxial InAs." Canadian Journal of Physics 74, S1 (December 1, 1996): 212–15. http://dx.doi.org/10.1139/p96-861.

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We report optical identification of the exciton–polariton in epitaxial InAs by combined photoluminescence, reflectance, and transmittance spectroscopy. The photoluminescence of these samples showed identifiable spectral lines a thousand times narrower than previously published results from other groups. The measurements were made at 1.4 K and at magnetic fields up to 7 T. Contrary to what is observed in other III–V semiconductors such as GaAs or InP, the free exciton (polariton) is nearly invisible in the photoluminescence spectrum without the application of a magnetic field. We believe that the relatively large residual donor concentration coupled with the large spatial extent of the exciton wave function in this material inhibit the existence of unbound excitonic recombination. Reflectance and transmittance spectroscopy provide very strong evidence that our identification is correct, and the magnetic field dependence yielded values of the electron effective mass and g-factor of (0.026 + 0.002)m0 and −15.3 ± 0.2, respectively, based on this assignment.

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8

Kono, Junichiro. "(Invited, Digital Presentation) Macroscopically Aligned Carbon Nanotubes for Photonics, Electronics, and Thermoelectrics." ECS Meeting Abstracts MA2022-01, no. 10 (July 7, 2022): 775. http://dx.doi.org/10.1149/ma2022-0110775mtgabs.

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The remarkable flexibility, stable chemical structure, and extraordinary thermal, electrical, and optical properties of carbon nanotubes (CNTs) are promising for a variety of applications in flexible and/or high-temperature electronics, optoelectronics, and thermoelectrics, including wearables, refractory photonics, and waste heat harvesting [1]. However, the long-standing goal in the preparation of CNT ensembles is how to maintain the extraordinary properties of individual CNTs on a macroscopic scale. The polydispersity and randomness remain two main challenges. Here, we will discuss different methods for creating macroscopically aligned CNTs, including spontaneous formation of wafer-scale aligned CNT films via controlled vacuum filtration [2-4] and production of ultrahigh-conductivity CNT fibers and films through solution spinning and coating [5,6]. We will then describe the optical [2,7-11], dc and ac electrical [2,12-17], thermal [18], and thermoelectric [19-21] properties of these materials. These results are promising for device applications in various fields such as flexible CNT broadband detectors [22-26], spectrally selective thermal emitters [11], and thermoelectric devices [20,21]. W. Gao et al., “Macroscopically Aligned Carbon Nanotubes for Flexible and High-Temperature Electronics, Optoelectronics, and Thermoelectrics,” Journal of Physics D: Applied Physics 53, 063001 (2020). X. He et al., “Wafer-Scale Monodomain Films of Spontaneously Aligned Single-Walled Carbon Nanotubes,” Nature Nanotechnology 11, 633 (2016). W. Gao and J. Kono, “Science and Applications of Wafer-Scale Crystalline Carbon Nanotube Films Prepared through Controlled Vacuum Filtration,” Royal Society Open Science 6, 181605 (2019). N. Komatsu et al., “Groove-Assisted Global Spontaneous Alignment of Carbon Nanotubes in Vacuum Filtration,” Nano Letters 20, 2332 (2020). N. Behabtu et al., “Strong, Light, Multifunctional Fibers of Carbon Nanotubes with Ultrahigh Conductivity,” Science 339, 182 (2013). L. W. Taylor et al., “Improved Properties, Increased Production, and the Path to Broad Adoption of Carbon Nanotube Fibers,” Carbon 171, 689 (2021). K. Yanagi et al., “Intersubband Plasmons in the Quantum Limit in Gated and Aligned Carbon Nanotubes,” Nature Communications 9, 1121 (2018). W. Gao et al., “Continuous Transition between Weak and Ultrastrong Coupling through Exceptional Points in Carbon Nanotube Microcavity Exciton–Polaritons,” Nature Photonics 12, 362 (2018). M. E. Green et al., “Bright and Ultrafast Photoelectron Emission from Aligned Single-Wall Carbon Nanotubes through Multiphoton Exciton Resonance,” Nano Letters 19, 158 (2019). F. Katsutani et al., “Direct Observation of Cross-Polarized Excitons in Aligned Single-Chirality Single-Wall Carbon Nanotubes,” Physical Review B 99, 035426 (2019). W. Gao et al., “Macroscopically Aligned Carbon Nanotubes as a Refractory Platform for Hyperbolic Thermal Emitters,” ACS Photonics 6, 1602 (2019). X. Wang et al., “High-Ampacity Power Cables of Tightly-Packed and Aligned Carbon Nanotubes,” Advanced Functional Materials 24, 3241 (2014). A. Zubair et al., “Carbon Nanotube Fiber Terahertz Polarizer,” Applied Physics Letters 108, 141107 (2016). D. Tristant et al., “Enlightening the Ultrahigh Electrical Conductivities of Doped Double-Wall Carbon Nanotube Fibers by Raman Spectroscopy and First-Principles Calculations,” Nanoscale 18, 19668 (2016). N. Komatsu et al., “Modulation-Doped Multiple Quantum Wells of Aligned Single-Wall Carbon Nanotubes,” Advanced Functional Materials 27, 1606022 (2017). F. R. G. Bagsican et al., “Terahertz Excitonics in Carbon Nanotubes: Exciton Autoionization and Multiplication,” Nano Letters 20, 3098 (2020). A. Baydin et al., “Giant Terahertz Polarization Rotation in Ultrathin Films of Aligned Carbon Nanotubes,” Optica 8, 760 (2021). S. Yamaguchi et al., “One-Directional Thermal Transport in Densely Aligned Single-Wall Carbon Nanotube Films,” Applied Physics Letters 115, 223104 (2019). K. Fukuhara et al., “Isotropic Seebeck Coefficient of Aligned Single-Wall Carbon Nanotube Films,” Applied Physics Letters 113, 243105 (2018). Y. Ichinose et al., “Solving the Thermoelectric Trade-Off Problem with Metallic Carbon Nanotubes,” Nano Letters 19, 7370 (2019). N. Komatsu et al., “Macroscopic Weavable Fibers of Carbon Nanotubes with Giant Thermoelectric Power Factor,” Nature Communications 12, 4931 (2021). S. Nanot et al., “Broadband, Polarization-Sensitive Photodetector Based on Optically-Thick Films of Macroscopically Long, Dense, and Aligned Carbon Nanotubes,” Scientific Reports 3, 1335 (2013). X. He et al., “Photothermoelectric p-n Junction Photodetector with Intrinsic Broadband Polarimetry Based on Macroscopic Carbon Nanotube Films,” ACS Nano 7, 7271 (2013). X. He et al., “Carbon Nanotube Terahertz Detector,” Nano Letters 14, 3953 (2014). X. He, F. Léonard, and J. Kono, “Uncooled Carbon Nanotube Photodetectors,” Advanced Optical Materials 3, 989 (2015). A. Zubair et al., “Carbon Nanotube Woven Textile Photodetector,” Physical Review Materials 2, 015201 (2018).

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9

SCHMIDT, T., L. WORSCHECH, M. SCHEIBNER, T. SLOBODSKYY, L. W. MOLENKAMP, and A. FORCHEL. "SPIN POLARIZATION IN SEMIMAGNETIC CdMnSe/ZnSe QUANTUM DOTS WITH ZERO EXCITON g FACTOR." International Journal of Modern Physics B 21, no. 08n09 (April 10, 2007): 1626–31. http://dx.doi.org/10.1142/s0217979207043324.

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We have investigated the degree of circular polarization (ρ) in the emission of semimagnetic CdMnSe/ZnSe quantum dots (QDs) with Mn contents of nominally 0, 1 and 2 %. Circularly polarized excitation was used to control the polarization of the excited carriers. The g factors were determined from the dependence of ρ on the magnetic field strength. We demonstrate that in QDs with 1 % Mn the exciton g factor is vanishingly small. We also present measurements on the excitation power dependent changes of the polarization. A direct heating mechanism is identified as origin of the drastic enhancement of the g factor by ramping up the excitation power. For high laser powers the exciton g factor increases by a factor of 30. In addition, by comparing the luminescence polarization of QDs with 2 % Mn and without Mn a sign reversal of the g factor was observed.

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10

Denis, Pascale L., Alina N. Stamate, and Michel Cossette. "L’effet de retest du facteur g en sélection du personnel." Humain et Organisation 7, no. 1 (June 22, 2022): 1–16. http://dx.doi.org/10.7202/1089953ar.

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11

Bernon, Florent. "Transfert des intègrales orbitales pour les algèbres de Lie classiques." Canadian Journal of Mathematics 61, no. 5 (October 1, 2009): 961–1049. http://dx.doi.org/10.4153/cjm-2009-049-x.

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RésuméDans cet article, on considère un groupe semi-simple $G$ classique réel et connexe. On suppose de plus que $G$ possède un sous-groupe de Cartan compact. On définit une famille de sous-algèbres de Lie associée à $\mathfrak{g}=\text{Lie(G)}$, de même rang que g dont tous les facteurs simples sont de rang 1 ou 2. Soit $\mathfrak{g}'$ une telle sous-algèbre de Lie. On construit alors une application de transfert des intégrales orbitales de $\mathfrak{g}'$ dans l’espace des intégrales orbitales de $\mathfrak{g}$. On montre que cette application est définie dès que $\mathfrak{g}$ne possède pas de facteur simple réel de type CI de rang supérieur ouégal à 3. Si de plus, $\mathfrak{g}$ ne possède pas de facteur simple de type BI de rang supérieur à 3, on montre la surjectivité de cette application de transfert.On utilise cette application de transfert pour obtenir une formule de réduction de l’intégrale de Cauchy Harish-Chandra pour les paires duales d’algèbres de Lie réductives $(U(p,q),U(r,s))$ et $(Sp(p,q),{{O}^{*}}(2n))$ avec $p+q=r+s=n$.

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12

Turyanska, L., R. J. A. Hill, O. Makarovsky, F. Moro, A. N. Knott, O. J. Larkin, A. Patanè, et al. "Tuneable paramagnetic susceptibility and exciton g-factor in Mn-doped PbS colloidal nanocrystals." Nanoscale 6, no. 15 (2014): 8919–25. http://dx.doi.org/10.1039/c4nr02336f.

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We report on PbS colloidal nanocrystals that combine within one structure solubility in physiological solvents with near-infrared photoluminescence, and magnetic (magnetic susceptibility) and optical (exciton g-factor) properties tuneable by the controlled incorporation of magnetic impurities (Mn).

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13

Burakowski, M., P. Mrowiński, M. Gawełczyk, J. P. Reithmaier, S. Höfling, and G. Sęk. "Diamagnetic coefficients and g-factors of InAs/InGaAlAs quantum dashes emitting at telecom wavelengths." Journal of Applied Physics 132, no. 14 (October 14, 2022): 144301. http://dx.doi.org/10.1063/5.0101345.

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Semiconductor nanostructures of various material systems are heavily researched for information processing applications as single-photon sources for communication and as a spin memory for storage. Here, exciton, electron, and hole properties in single InAs/InP asymmetric quantum dots (quantum dashes) emitting in a broad spectral range from 0.8 to above 1 eV are studied experimentally and theoretically. Experiments using magneto-microphotoluminescence allowed us to determine g-factor tensor components and diamagnetic coefficients. The growth-axis exciton g-factor is in a 0.0–2.9 range with a constant hole g-factor of 4.5 and variation governed by electron contribution. The in-plane g-factor is more stable with the size of the nanostructure exhibiting values of around −0.7 and −1.6 for holes and electrons, respectively. The diamagnetic coefficients are [Formula: see text] and [Formula: see text] in the growth and in-plane directions, respectively. Simulations based on the eight-band k⋅p model qualitatively reproduce the key experimental features, including the vanishing of the inverse fine-structure splitting of bright exciton at around 3 T, making these structures prospective for the generation of entangled photons.

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14

Klotz, F., V. Jovanov, J. Kierig, E. C. Clark, D. Rudolph, D. Heiss, M. Bichler, G. Abstreiter, M. S. Brandt, and J. J. Finley. "Observation of an electrically tunable exciton g factor in InGaAs/GaAs quantum dots." Applied Physics Letters 96, no. 5 (February 2010): 053113. http://dx.doi.org/10.1063/1.3309684.

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15

Quax, G. W. W., T. E. J. Campbell Ricketts, A. M. Yakunin, T. van Lippen, R. Nötzel, P. M. Koenraad, C. A. C. Bosco, J. H. H. Rietjens, B. Koopmans, and A. Yu Silov. "All-optical control of the exciton g-factor in InAs/GaAs quantum dots." Physica E: Low-dimensional Systems and Nanostructures 40, no. 6 (April 2008): 1832–35. http://dx.doi.org/10.1016/j.physe.2007.10.089.

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16

Baudin, J. P., and A. F. Fritsch. "Influence de la température sur l'accumulation par la voie directe du 60Co chez un poisson dulçaquicole." Revue des sciences de l'eau 1, no. 4 (April 12, 2005): 385–400. http://dx.doi.org/10.7202/705018ar.

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L'influence du facteur thermique sur la contamination de la carpe par le 60Co a été étudiée pour 4 températures : 8 °C, 15 °C, 20 °C et 25 °C. Pour chaque expérience, un lot homogène de 10 individus, d'une masse initiale d'environ 2,3 g et nourris ad libitum, est introduit dans 5 litres d'eau, renouvelée tous les 3 à 4 jours et contaminée à raison de 1,2.105 Bq.l-1. Entre deux renouvellements, la concentration du 60Co dans l'eau décroît sensiblement et l'état ionique du radionucléide, introduit à 100 % sous forme cationique, évolue vers des formes anioniques et neutres. Ces deux faits sont liés au métabolisme des poissons dont la croissance pondérale est corrélée à la température, la distribution de la nourriture étant adaptée aux besoins des individus. Globalement, la quantité totale de radiocobalt fixée par les carpes apparaît très fortement liée au facteur thermique mais, selon le niveau des températures, des situations différentes se dégagent pour des mêmes écarts. Il n'y a pas proportionnalité comptéte entre élévation de température et accumulation du 60Co mais une augmentation discontinue témoignant de l'existence de paliers, dont le plus important se situe à 20 °C.Le facteur de concentration du 60Co est, par contre, peu influencé par le facteur thermique pour les écarts inférieurs à 10 °C ou quand la température maximale est inférieure à 20 °C. L'incidence de la température devient sensible quand les écarts dépassent 10 °C et notamment lorsque sont atteintes des valeurs correspondant à l'optimum thermique des carpes. A l'équilibre, le facteur de concentration moyen du 60Co est de 3,6 à 8 °C, 4,4 à 15 °C, 5,1 à 20 °C et 6 à 25 °C.

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17

Hanine, Ilyas. "L’ACV : la méthodologie internationale du calcul d’impact de la production d’énergie." Revue Générale Nucléaire, no. 4 (2022): 52–53. http://dx.doi.org/10.1051/rgn/20224052.

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Dans une récente étude parue cet été, EDF met à jour le facteur d’émission du parc nucléaire français à 3,7 g éq. CO2/kWh, faisant de l’atome le moyen le plus décarboné de produire de l’électricité du point de vue climatique. Ce chiffre, obtenu par une analyse en cycle de vie (ACV), repose sur une méthodologie normalisée au niveau international.

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18

Zhai, Yaxin, Chuanxiang Sheng, and Z. Valy Vardeny. "Singlet fission of hot excitons in π -conjugated polymers." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 373, no. 2044 (June 28, 2015): 20140327. http://dx.doi.org/10.1098/rsta.2014.0327.

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We used steady-state photoinduced absorption (PA), excitation dependence (EXPA( ω )) spectrum of the triplet exciton PA band, and its magneto-PA (MPA( B )) response to investigate singlet fission (SF) of hot excitons into two separated triplet excitons, in two luminescent and non-luminescent π -conjugated polymers. From the high energy step in the triplet EXPA( ω ) spectrum of the luminescent polymer poly(dioctyloxy)phenylenevinylene (DOO-PPV) films, we identified a hot-exciton SF (HE-SF) process having threshold energy at E ≈2 E T (=2.8 eV, where E T is the energy of the lowest lying triplet exciton), which is about 0.8 eV above the lowest singlet exciton energy. The HE-SF process was confirmed by the triplet MPA( B ) response for excitation at E >2 E T , which shows typical SF response. This process is missing in DOO-PPV solution, showing that it is predominantly interchain in nature. By contrast, the triplet EXPA( ω ) spectrum in the non-luminescent polymer polydiacetylene (PDA) is flat with an onset at E = E g (≈2.25 eV). From this, we infer that intrachain SF that involves a triplet–triplet pair state, also known as the ‘dark’ 2A g exciton, dominates the triplet photogeneration in PDA polymer as E g >2 E T . The intrachain SF process was also identified from the MPA( B ) response of the triplet PA band in PDA. Our work shows that the SF process in π -conjugated polymers is a much more general process than thought previously.

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19

Nozue, Y., Z. K. Tang, and T. Goto. "Excitons in PbI2 clusters incorporated into zeolite cages." Solid State Communications 73, no. 8 (February 1990): 531–34. http://dx.doi.org/10.1016/0038-1098(90)91043-g.

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20

Coppejans-Desmedt, H. "G. Kurgan-van Hentenryk, J. Stengers, L'innovation technologique. Facteur de changement (XIXe-XXe siècles)." BMGN - Low Countries Historical Review 103, no. 2 (January 1, 1988): 271. http://dx.doi.org/10.18352/bmgn-lchr.2949.

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21

Vadot, W., K. Garambois, O. Detante, A. Jaillard, and M. Hommel. "G - 65 Tolérance en pratique clinique du facteur VII recombinant dans l’hématome intracérébral primitif." Revue Neurologique 163, no. 4 (April 2007): 48–49. http://dx.doi.org/10.1016/s0035-3787(07)90571-8.

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22

Rapaport, R., A. Qarry, E. Cohen, A. Ron, and L. N. Pfeiffer. "Charged Excitons and Cavity Polaritons." physica status solidi (b) 227, no. 2 (October 2001): 419–27. http://dx.doi.org/10.1002/1521-3951(200110)227:2<419::aid-pssb419>3.0.co;2-g.

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23

Chumachenko, V. A., A. P. Naumenko, O. A. Yeshchenko, N. V. Kutsevol, and I. S. Bondarchuk. "Synthesis, Morphology, and Optical Properties of Au/CdS Hybrid Nanocomposites Stabilized by Branched Polymer Matrices." Journal of Nanomaterials 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/1439437.

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Metal/semiconductor (Au/CdS) nanocomposites were synthesized in the solution of branched D-g-PAA polymer. TEM and DLS of Au/CdS/D-g-PAA nanocomposites revealed complicated nanocomposite structure consisting of the Au nanoparticles (NPs) of 6 nm in size surrounded by small CdS NPs with size of 3 nm. These nanocomposites formed the aggregates-clusters with average size of 50–800 nm. Absorption spectra of Au/CdS nanocomposites consist of the bands of excitons in CdS NPs and surface plasmons in Au ones. The surface plasmon band of gold NPs is red shifted and broadened in Au/CdS/D-g-PAA nanocomposites comparing to the one of Au NPs in Au/D-g-PAA proving the fact of close location of CdS and Au NPs in the synthesized Au/CdS/D-g-PAA nanocomposites. The PL spectra of Au/CdS nanocomposites originate from the radiative transitions in excitons in CdS NPs. The 4-fold increase of intensity of free exciton PL is observed for CdS NPs in Au/CdS/D-g-PAA comparing to CdS ones in CdS/D-g-PAA that is due to PL enhancement by local field of surface plasmons of Au NPs. Also, the 12-fold decrease of intensity of localized exciton PL is observed for CdS NPs in Au/CdS/D-g-PAA comparing to CdS ones in CdS/D-g-PAA. Most probably, it is due to passivation of the surface of CdS NPs carried out by the Au ones.

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Zhang, Dan, Guoqiang Tan, Min Wang, Bin Li, Mingyue Dang, Huijun Ren, and Ao Xia. "The modulation of g-C3N4 energy band structure by excitons capture and dissociation." Materials Research Bulletin 122 (February 2020): 110685. http://dx.doi.org/10.1016/j.materresbull.2019.110685.

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25

Sahraoui, Naima, Nassim Moula, Saliha Boudjenah, and Jean-Luc Hornick. "Teneur en minéraux principaux de la viande cameline en Algérie." Revue d’élevage et de médecine vétérinaire des pays tropicaux 71, no. 4 (January 25, 2019): 163. http://dx.doi.org/10.19182/remvt.31672.

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L’objectif de l’étude était de déterminer les concentrations en minéraux et en oligoéléments de la viande de dromadaire en Algérie. Des échantillons de viande de 32 dromadaires ont été recueillis. Les dosages ont été réalisés par spectroscopie d’émission atomique. Les concentrations moyennes (± erreur type) en calcium et en phosphore ont été respectivement de 33,1 ± 6,1 et 655 ± 21,3 mg / 100 g. Les teneurs en oligoéléments ont été de 14 056 ± 831 µg / 100 g pour le zinc, 6100 ± 447 µg / 100 g pour le fer, et 1322 ± 43 µg / 100 g pour le cuivre. Le facteur race a eu un effet très significatif (p < 0,001) sur les teneurs en calcium et en sodium. Aucun effet significatif (p < 0,05) de l’âge n’a été observé sur les différents minéraux étudiés. La viande de dromadaire présente des teneurs en minéraux proches de celles des autres animaux de rente.

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Delalande, C. "Excitons and type I – type II transition under magnetic fields." Superlattices and Microstructures 12, no. 3 (January 1992): 387–91. http://dx.doi.org/10.1016/0749-6036(92)90288-g.

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Lawal-Are, A. O., R. O. Moruf, F. L. Ojeah, L. O. Taiwo, and O. E. Aligbe. "Weight yield factor, chemical composition and energy value in three imported shellfish species in Nigeria." Nigerian Journal of Animal Production 48, no. 3 (March 6, 2021): 63–70. http://dx.doi.org/10.51791/njap.v48i3.2967.

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Shellfish is a major component of our global aquatic food supply, which includes the molluscs, crustaceans and echinoderms. The aim of this study was to evaluate the weight yield factor, chemical composition and energy value in three imported shellfish species (Palinurus regius, Sepia officinalis and Farfantepenaeus notialis) in Nigeria. The physical and chemical determinations were in accordance with the official methods. The results showed that all the shellfish species had weight yield factor less than 1, and the weights obtained for the samples showed no statistically significant differences before and after boiling. In raw samples, S. officinalis had significant (p<0.05) higher protein and crude fat values of 20.41±0.63 g/100 g and 2.67±0.68 g/100 g respectively. In boiled samples, high protein levels (15.21-19.22 g/100 g) with no significant difference characterized the overall proximate profile of shellfish species studied herein. In terms of minerals, all investigated elements (calcium, magnesium, potassium, phosphorus and sodium) were generally found at lower levels in boiled samples when compared with the mineral contents of the raw shellfish samples. S. officinalis had the higher total energy value in both raw (344.94 kJ 100/g) and boiled samples (373.96 kJ 100/g). All the species can be considered as food items with interesting dietetic properties due to high contents of proteins, minerals and useful energy values. Les mollusques et crustacés sont une composante importante de notre approvisionnement alimentaire aquatique mondial, qui comprend les mollusques, les crustacés et les échinodermes. L'objectif de cette étude était d'évaluer le facteur de rendement pondération, la composition chimique et la valeur énergétique de trois espèces importées de mollusques et crustacés (Palinurus regius, Sepia officinalis et Farfantepenaeus notialis) au Nigéria. Les déterminations physiques et chimiques étaient conformes aux méthodes officielles. Les résultats ont montré que toutes les espèces de mollusques et crustacés avaient un facteur de rendement de poids inférieur à 1, et les poids obtenus pour les échantillons n'ont montré aucune différence statistiquement significative avant et après l'ébullition. Dans les échantillons crus, S. officinalis avait des valeurs significatives (p<0.05) de protéines et de matières grasses brutes de 20.41±0.63 g/100 g et 2.67±0.68 g/100 g respectivement. Dans les échantillons bouillis, des niveaux élevés de protéines (15.21-19.22 g/100 g) sans différence significative ont caractérisé le profil proximate global des espèces de mollusques et crustacés étudiées dans le présente. En ce qui concerne les minéraux, tous les éléments étudiés (calcium, magnésium, potassium, phosphore et sodium) ont généralement été trouvés à des niveaux inférieurs dans les échantillons bouillis par rapport au contenu minéral des échantillons de mollusques et crustacés crus. S. officinalis avait la valeur énergétique totale la plus élevée dans les échantillons bruts (344.94 kJ 100/g) et bouillis (373.96 kJ 100/g). Toutes les espèces peuvent être considérées comme des aliments aux propriétés diététiques intéressantes en raison de la teneur élevée en protéines, minéraux et valeurs énergétiques utiles.

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Bédu, A., P. Rohrlich, C. Farnoux, M. Duval, O. Fenneteau, C. Boissinot, D. Pinquier, J. Cartron, E. Vilmer, and Y. Aujard. "Neutropénies allo-immunes néonatales. Intérêt du traitement par facteur de croissance granuleux (G-CSF). Deux nouvelles observations." Archives de Pédiatrie 6, no. 12 (December 1999): 1297–301. http://dx.doi.org/10.1016/s0929-693x(00)88892-2.

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29

Khiari, M., S. Amara, I. Chaar, D. Lounissi, M. Dhraeif, A. M. Ben Hamida, L. Ggharbi, S. Mzabi Regaya, and S. Bouraoui. "Le polymorphisme -347 G>GA du promoteur du gène CDH1 : est-il un facteur de prédisposition ou un facteur pronostique dans le cancer colorectal sporadique chez la population tunisienne ?" Annales de Pathologie 32, no. 5 (November 2012): S161. http://dx.doi.org/10.1016/j.annpat.2012.09.049.

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30

Mariette, H., R. Triboulet, and Y. Marfaing. "Alloy-trapped excitons in a new II–VI semiconductor solid solution Hg1−xZnxTe." Journal of Crystal Growth 86, no. 1-4 (January 1988): 558–63. http://dx.doi.org/10.1016/0022-0248(90)90775-g.

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31

Kumar, N. R. Senthil, and A. John Peter. "Pressure Induced Effective Exciton g-Factor in a Strained Ga_0.2In_0.8As/GaAs Quantum Dot." Journal of Advanced Physics 4, no. 3 (September 1, 2015): 191–98. http://dx.doi.org/10.1166/jap.2015.1190.

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32

Lalitha, D., A. John Peter, and Chang Kyoo Yoo. "Effects of sp-d exchange on a bound polaron and the g-factor of the exciton in a GaMnAs quantum dot." Superlattices and Microstructures 60 (August 2013): 453–61. http://dx.doi.org/10.1016/j.spmi.2013.05.031.

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33

Faria Junior, Paulo E., and Jaroslav Fabian. "Signatures of Electric Field and Layer Separation Effects on the Spin-Valley Physics of MoSe2/WSe2 Heterobilayers: From Energy Bands to Dipolar Excitons." Nanomaterials 13, no. 7 (March 27, 2023): 1187. http://dx.doi.org/10.3390/nano13071187.

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Multilayered van der Waals heterostructures based on transition metal dichalcogenides are suitable platforms on which to study interlayer (dipolar) excitons, in which electrons and holes are localized in different layers. Interestingly, these excitonic complexes exhibit pronounced valley Zeeman signatures, but how their spin-valley physics can be further altered due to external parameters—such as electric field and interlayer separation—remains largely unexplored. Here, we perform a systematic analysis of the spin-valley physics in MoSe2/WSe2 heterobilayers under the influence of an external electric field and changes of the interlayer separation. In particular, we analyze the spin (Sz) and orbital (Lz) degrees of freedom, and the symmetry properties of the relevant band edges (at K, Q, and Γ points) of high-symmetry stackings at 0° (R-type) and 60° (H-type) angles—the important building blocks present in moiré or atomically reconstructed structures. We reveal distinct hybridization signatures on the spin and the orbital degrees of freedom of low-energy bands, due to the wave function mixing between the layers, which are stacking-dependent, and can be further modified by electric field and interlayer distance variation. We find that H-type stackings favor large changes in the g-factors as a function of the electric field, e.g., from −5 to 3 in the valence bands of the Hhh stacking, because of the opposite orientation of Sz and Lz of the individual monolayers. For the low-energy dipolar excitons (direct and indirect in k-space), we quantify the electric dipole moments and polarizabilities, reflecting the layer delocalization of the constituent bands. Furthermore, our results show that direct dipolar excitons carry a robust valley Zeeman effect nearly independent of the electric field, but tunable by the interlayer distance, which can be rendered experimentally accessible via applied external pressure. For the momentum-indirect dipolar excitons, our symmetry analysis indicates that phonon-mediated optical processes can easily take place. In particular, for the indirect excitons with conduction bands at the Q point for H-type stackings, we find marked variations of the valley Zeeman (∼4) as a function of the electric field, which notably stands out from the other dipolar exciton species. Our analysis suggests that stronger signatures of the coupled spin-valley physics are favored in H-type stackings, which can be experimentally investigated in samples with twist angle close to 60°. In summary, our study provides fundamental microscopic insights into the spin-valley physics of van der Waals heterostructures, which are relevant to understanding the valley Zeeman splitting of dipolar excitonic complexes, and also intralayer excitons.

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34

Li, Shulun, Xiangjun Shang, Yao Chen, Xiangbin Su, Huiming Hao, Hanqing Liu, Yu Zhang, Haiqiao Ni, and Zhichuan Niu. "Wet-Etched Microlens Array for 200 nm Spatial Isolation of Epitaxial Single QDs and 80 nm Broadband Enhancement of Their Quantum Light Extraction." Nanomaterials 11, no. 5 (April 27, 2021): 1136. http://dx.doi.org/10.3390/nano11051136.

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Uniform arrays of three shapes (gauss, hat, and peak) of GaAs microlenses (MLs) by wet-etching are demonstrated, ∼200 nm spatial isolation of epitaxial single QDs embedded (λ: 890–990 nm) and broadband (Δλ∼80 nm) enhancement of their quantum light extraction are obtained, which is also suitable for telecom-band epitaxial QDs. Combined with the bottom distributed Bragg reflector, the hat-shaped ML forms a cavity and achieves the best enhancement: extraction efficiency of 26%, Purcell factor of 2 and single-photon count rate of 7×106 counts per second at the first lens; while the gauss-shaped ML shows a broader band (e.g., longer λ) enhancement. In the MLs, single QDs with featured exciton emissions are observed, whose time correlations prove single-photon emission with multi-photon probability g(2)(0)=0.02; some QDs show both biexciton XX and exciton X emissions and exhibit a perfect cascade feature. This work could pave a step towards a scalable array of QD single-photon sources and the application of QD photon-pair emission for entanglement experiments.

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35

Jegerlehner, Fred. "The role of mesons in muon g − 2." EPJ Web of Conferences 199 (2019): 01010. http://dx.doi.org/10.1051/epjconf/201919901010.

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The muon anomaly aμ=(gμ-2)/2 showing a persisting 3 to 4 σ deviation between the SM prediction and the experiment is one of the most promising signals for physics beyond the SM. As is well known, the hadronic uncertainties are limiting the accuracy of the Standard Model prediction. Therefore a big effort is going on to improve the evaluations of hadronic effects in order to keep up with the 4-fold improved precision expected from the new Fermilab measurement in the near future. A novel complementary type experiment planned at J-PARC in Japan, operating with ultra cold muons, is expected to be able to achieve the same accuracy but with completely different systematics. So exciting times in searching for New Physics are under way. I discuss the role of meson physics in calculations of the hadronic part of the muon g-2. The improvement is expected to substantiate the present deviation $\Delta a_\mu ^{{\rm{New}}\,{\rm{physics}}} = \Delta a_\mu ^{{\rm{Experiment}}} - \Delta a_\mu ^{{\rm{Standard Model}}}$ to a 6 to 10 standard deviation effect, provided hadronic uncertainties can be reduce by a factor two. This concerns the hadronic vacuum polarization as well as the hadronic light-by-light scattering contributions, both to a large extent determined by the low lying meson spectrum. Better meson production data and progress in modeling meson form factors could greatly help to improve the precision and reliability of the SM prediction of aμ and thereby provide more information on what is missing in the SM.

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Jursenas, S., A. Gruodis, G. Kodis, and L. Valkūnas. "Spectroscopy of excitons in the polar molecular crystal DMABI." Advanced Materials for Optics and Electronics 6, no. 56 (September 1996): 387–90. http://dx.doi.org/10.1002/(sici)1099-0712(199609)6:5/6<387::aid-amo263>3.0.co;2-g.

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37

DUBEUF, B., J. B. COULON, and E. LANDAIS. "Mise à l’herbe des vaches laitières en zone de montagne : description des pratiques et liaison avec les performances laitières." INRAE Productions Animales 4, no. 5 (December 2, 1991): 373–81. http://dx.doi.org/10.20870/productions-animales.1991.4.5.4351.

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46 exploitations laitières des Alpes du Nord ont été classées à l’aide d’une typologie des systèmes de pratiques de mise à l’herbe. Les variations de la production laitière et de la composition chimique des laits de troupeau ont été observées dans chacun des types au cours de cette période. A la mise à l’herbe, la production et la composition du lait ont varié de manière importante, mais différente selon les types (- 0,5 à + 2,9 g/kg de taux protéique entre la 3e semaine avant la mise à l’herbe et la 3e semaine après ; - 1,6 à + 3,5 g/kg de taux butyreux ; + 1,6 à + 2,3 kg/j de lait). La maîtrise de l’alimentation hivernale est un facteur majeur des variations des taux protéiques et butyreux, alors que les pratiques de mise à l’herbe n’en modifient que faiblement l’amplitude. Les pratiques de gestion du système fourrager au printemps ont surtout une influence sur les ressources fourragères ultérieures. La maîtrise de l’alimentation des vaches laitières au pâturage est très liée à celle de l’alimentation hivernale.

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38

Chen, Y. H., X. L. Ye, B. Xu, Z. G. Wang, and Z. Yang. "Large g factors of higher-lying excitons detected with reflectance difference spectroscopy in GaAs-based quantum wells." Applied Physics Letters 89, no. 5 (July 31, 2006): 051903. http://dx.doi.org/10.1063/1.2245213.

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39

Rebane, Y. T., Y. G. Shreter, and M. Albrecht. "Stacking Faults as Quantum Wells for Excitons in Wurtzite GaN." physica status solidi (a) 164, no. 1 (November 1997): 141–44. http://dx.doi.org/10.1002/1521-396x(199711)164:1<141::aid-pssa141>3.0.co;2-g.

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40

TOULMONDE, VINCENT. "COMPORTEMENT AU VOISINAGE DE 1 DE LA FONCTION DE RÉPARTITION DE φ(n)/n." International Journal of Number Theory 05, no. 08 (December 2009): 1347–84. http://dx.doi.org/10.1142/s1793042109001414.

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Let φ denote Euler's totient function, and G be the distribution function of φ(n)/n. Using functional equations, it is shown that φ(n)/n is statistically close to 1 essentially when prime factors of n are large. A function defined by a difference-differential equation gives a quantitative measure of the statistical influence of the size of prime factors of n on the closeness of φ(n)/n to 1. As a corollary, an asymptotic expansion at any order of G(1)-G(1-ε) is obtained according to negative powers of log (1/ε), when ε tends to 0+. This improves a result of Erdős (1946) in which he gives the first term of it. By optimally choosing the order of this expansion, an estimation of G(1)-G(1-ε) is deduced, involving an error term of the same size as the best known error term involved in prime number theorem. Soit φ l'indicatrice d'Euler. Nous étudions le comportement au voisinage de 1 de la fonction G de répartition de φ(n)/n, via la mise en évidence d'équations fonctionnelles. Nous obtenons un résultat mesurant l'influence statistique de la taille du plus petit facteur premier d'un entier générique n quant à la proximité de φ(n)/n par rapport à 1. Ce résultat met en jeu une fonction définie par une équation différentielle aux différences. Nous en déduisons un développement limité à tout ordre de G(1)-G(1-ε) selon les puissances de 1/(log 1/ε), améliorant ainsi un résultat d'Erdős (1946) dans lequel il obtient le premier terme de ce développement. Une troncature convenable de ce développement fournit un terme d'erreur comparable à celui actuellement connu pour le théorème des nombres premiers.

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41

Aguinaga, David, Mireia Casanovas, Rafael Rivas-Santisteban, Irene Reyes-Resina, Gemma Navarro, and Rafael Franco. "The sigma-1 receptor as key common factor in cocaine and food-seeking behaviors." Journal of Molecular Endocrinology 63, no. 4 (November 2019): R81—R92. http://dx.doi.org/10.1530/jme-19-0138.

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Addiction and eating disorders involve brain reward circuits. Binge eating predisposes to addictive behavior, while the cessation of exposure to drugs of abuse leads to reward activities, including intake of tasty foods. Cocaine use is associated with a decrease in food intake, with reversal after drug use is discontinued. Exciting new findings show that receptors for the ‘hunger’ hormone, ghrelin, directly interact with the sigma-1 receptor (σ1R), which is a target of cocaine. σ1Rs are key players in regulating dopaminergic neurotransmission and ghrelin-mediated actions. This review focuses on the σ1 receptor as a general neuroendocrine regulator by directly interacting with neuronal G-protein-coupled receptors. This review also covers the early mechanisms by which cocaine binding to σ1 blocks the food-seeking behavior triggered by ghrelin. Those findings appear as fundamental to understand common mechanisms in drug addiction and eating disorders.

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42

LAPERSONNE-MEYER, C. "EXCITONS ON A 1D PERIODIC CONJUGATED POLYMER CHAIN: TWO ELECTRONIC STRUCTURES OF POLYDIACETYLENE CHAINS." International Journal of Modern Physics B 15, no. 28n30 (December 10, 2001): 3593–96. http://dx.doi.org/10.1142/s0217979201008226.

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Crystalline polydiacetylenes (PDA) provide a model system for conjugated polymers. Monomer crystals where the polymer content is very low give access to the electronic structure of a 1D straight periodic isolated chain. PDA are known to exist as crystals in two electronic structures, the so-called 'blue' and 'red' phases. In 3BCMU crystals, blue and red chains coexist, so that the electronic properties of both types of chains in the same environment can be compared. In both cases fluorescence originates from the 1 B u exciton state. The blue exciton lifetime is 140 fs, its fluorescence quantum yield is small (10-4) and the relaxation is dominated by non radiative processes via low lying A g states as in polyenes. On the contrary, for red chains the exciton state is highly fluorescent (quantum yield 0.30), its lifetime is 52 ps at 15 K, implying a short radiative lifetime <100 ps. Recent results on the temperature dependence of lifetime and fluorescence yield imply the presence of states, thermally accessible from the exciton state, but non radiant to the ground state. This is consistent with a non planar conformation of the chain.

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43

Li, Gaoyuan. "The Anomalous Magnetic Moment of Muon." Journal of Physics: Conference Series 2381, no. 1 (December 1, 2022): 012022. http://dx.doi.org/10.1088/1742-6596/2381/1/012022.

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Abstract Known as one of the most hopeful fields to find new physics beyond the standard model, the anomalous magnetic moment of muon has gained much attention for a long time and become even more important after the Fermi National Accelerator Laboratory’s result came out in 2018. This paper shows the general works and achievements in this exciting field. Those include experiments operated by the Brookhaven National Laboratory and Fermi National Accelerator Laboratory to measure the g-2 factor, the calculation based on the standard model, and a possible extension of the standard model that can explain the experimental results. This paper is an introduction for anyone interested in this field.

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44

Sow, Baïdy, Bertrand Tchanche, Ibrahima Fall, Saliou Souare, and Aminata Mbow-Diokhane. "Pollution atmosphérique dans la ville de Dakar, Sénégal." La Météorologie, no. 116 (2022): 048. http://dx.doi.org/10.37053/lameteorologie-2022-0013.

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La pollution atmosphérique est une menace pour la santé humaine et l'environnement avec des conséquences économiques et sociales considérables. Elle fait l'objet de nombreuses études à travers le monde, et en particulier dans les pays développés où des politiques de réduction des émissions de polluants sont progressivement mises en place. Les pays en développement, à l'instar du Sénégal, sont en retard et peinent à s'organiser pour préserver la qualité de l'air. L'absence de données relatives au suivi de la qualité de l'air et la faible prise en compte des émissions de polluants dans les secteurs des transports et de l'industrie ont amené le gouvernement du Sénégal à mettre en place en 2009 le centre de gestion de la qualité de l'air (CGQA). Les particules en suspension (PM10 et PM2.5) sont les polluants les plus importants observés à Dakar et leurs concentrations dépassent les seuils annuels fixés par l'Organisation mondiale de la santé (OMS) (PM10 : 20 μg m-3 et PM2.5 : 10 μg m-3) avec un facteur de 6 à 9 pour les PM10 et un facteur de 2 à 5 pour les PM2.5. Comme conséquence, l'indice de la qualité de l'air (IQA) varie de mauvais (100 ≤ IQA < 200) à très mauvais (IQA ≥ 200) durant la saison sèche (novembre à mai) qui occupe la majeure partie de l'année. Les indices favorables, bon (IQA < 50) à moyen (50 ≤ IQA < 100), sont obtenus durant la période de juin à octobre. En particulier l'IQA est en général bon durant la saison des pluies (août et septembre). Air pollution is a threat to human health and the environment with significant economic and social consequences. It is the subject of numerous studies throughout the world, and particularly in developed countries where policies to reduce pollutant emissions are being progressively implemented. Developing countries, like Senegal, are lagging behind and struggling to organize to preserve air quality. The lack of data on air quality monitoring and the low coverage of pollutant emissions in the transport sector and industry led the Government of Senegal to establish the Air Quality Management Center (CGQA0 : Centre de Gestion de la Qualité de l'Air) in 2009. PM10 and PM2.5 are the most important pollutants observed in Dakar and their concentrations exceed the annual thresholds set by the World Health Organization (WHO) (PM10 : 20 μg m-3 and PM2.50 : 10 μg m-3) with a factor of 6 to 9 for PM10 and a factor of 2 to 5 for PM2.5. As a result, the air quality index (AQI) varies from the bad (100 ≤AQI < 200) to the very bad (AQI≥200) during the main dry season (November to May) part of the year. The favourable, good (AQI < 50) to moderate (50 ≤ AQI < 100) indices are obtained during the period from June to October. In particular, the AQI is globally good during the rainy season (August to September).

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Shornikova, Elena V., Louis Biadala, Dmitri R. Yakovlev, Donghai Feng, Victor F. Sapega, Nathan Flipo, Aleksandr A. Golovatenko, et al. "Electron and Hole g-Factors and Spin Dynamics of Negatively Charged Excitons in CdSe/CdS Colloidal Nanoplatelets with Thick Shells." Nano Letters 18, no. 1 (November 28, 2017): 373–80. http://dx.doi.org/10.1021/acs.nanolett.7b04203.

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46

Gbedie, Nadré A., Kouakou T. Kouadio, Yaya Ouattara, Klotioloma Coulibaly, Bouadou Bonsson, Drolet J. M. Sery, Hyacinthe N. Legnate, and Jules Z. Kéli. "Evaluation de clones de colatiers (Cola nitida [Vent.] Schott et Endlicher) pour leur tolérance à la maladie du balai de sorcière du colatier en Côte d’Ivoire." International Journal of Biological and Chemical Sciences 13, no. 7 (February 14, 2020): 3347–54. http://dx.doi.org/10.4314/ijbcs.v13i7.29.

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La maladie du balai de sorcière du colatier est la maladie la plus importante du colatier car elle engendre d’énormes pertes de production. L’objectif principal de cette étude était d’identifier des clones de colatiers d’origine ivoirienne qui affichent le meilleur profil de tolérance à la maladie du balai de sorcière et ayant des paramètres de rendement intéressants. Pour atteindre cet objectif, un dispositif expérimental en bloc complètement randomisé à 3 répétitions a été utilisé et le facteur étudié est le clone avec 13 modalités. Les résultats obtenus montrent que 5 clones (clones 305, 314, 318, A2 et A3) n’ont pas subi d’attaque de la maladie. Les clones 311, 313, 315, 321 et 322 ont été moyennement attaqués. Sur la base des paramètres de rendement tels que le poids des noix par follicule et le nombre de noix par follicule, les clones 313 et 323 ont produit les plus grosses noix dont le poids moyen varie entre 31,98±11,60 g et 34,97±8,54 g et le clone 316 a donné un plus grand nombre de noix par follicule (en moyenne, 10,63±1,55 noix par follicules). Une classification combinant le niveau de tolérance des clones et les paramètres de rendement étudiés ont permis d’identifier les clones 313, 322 et 323 comme étant les meilleurs.Mots clés : Maladie du balai de sorcière, colatier, pertes de production, rendement.

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Wagner, H. P., H. P. Tranitz, R. Schuster, R. Engelhardt, U. W. Pohl, and D. Bimberg. "Thermal Activation and Phase Relaxation of Excitons in CdSe/ZnSSe Quantum Island Structures." physica status solidi (b) 224, no. 1 (March 2001): 195–99. http://dx.doi.org/10.1002/1521-3951(200103)224:1<195::aid-pssb195>3.0.co;2-g.

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48

Boucher-Gagnon, Magalie, Catherine des Rivières-Pigeon, and Nathalie Poirier. "L’implication des mères québécoises dans l’intégration scolaire en classe ordinaire de leur enfant ayant un TSA." Revue de psychoéducation 45, no. 2 (February 23, 2017): 313–41. http://dx.doi.org/10.7202/1039052ar.

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L’implication parentale est un facteur essentiel pour favoriser l’évolution positive d’un enfant présentant un TSA intégré en classe ordinaire. Or, aucune recherche québécoise n’a abordé ce sujet. L’objectif de cet article est donc d’identifier les différentes formes d’implication adoptées par les mères dans le contexte d’intégration en classe ordinaire au primaire de leur enfant ayant un TSA. À partir des dix-huit entretiens réalisés avec ces mères, nous avons fait une analyse qualitative thématique telle que proposée par Braun et Clark (2006). Les résultats font ressortir sept formes d’implication maternelle : (a) la préparation de l’enfant à l’entrée à l’école, (b) la recherche et la transmission des connaissances, (c) la participation au plan d’intervention, (d) la négociation et la revendication des services nécessaires pour l’enfant, (e) la continuité des apprentissages à la maison, (f) l’investissement de temps et d’argent et, finalement, (g) l’accompagnement de l’enfant à l’école. Ces résultats mettent en évidence que l’implication maternelle lors de l’intégration scolaire d’un enfant présentant un TSA peut prendre diverses formes et que plusieurs d’entre elles n’ont jamais fait l’objet de recherches.

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Graham, Matt Werden. "(Invited) Controlling Interlayer Stacking Configuration to Optimize Exciton Extraction Pathways in Van Der Waals Materials." ECS Meeting Abstracts MA2022-01, no. 12 (July 7, 2022): 862. http://dx.doi.org/10.1149/ma2022-0112862mtgabs.

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Abstract:

Employing ultrafast microscopy methods, we demonstrate how tuning the interlayer coupling by twisting stacking orientations results in different metastable electronic states like Moiré excitons in twisted bilayer graphene (tBLG) and bound triplet pairs (TT) in molecular crystals. Considering first tBLG, we show how stacking-angle tunable absorption resonances form a strongly-bound exciton state due to the interlayer orbitals' symmetric rehybridization. Using two-photon photoluminescence and intraband-transient absorption (TA) microscopies, we have imaged the photoemission and exciton dynamics from single-grains of tBLG. After resonant excitation, our results suggest the formation of strongly bound (up to 690 meV), metastable interlayer exciton states.[1] Our observation of resonant PL emission from twisted bilayer graphene materials is best explained by the theoretically predicted coexistence of strongly bound interlayer excitons and metallic graphene continuum states to form Moiré excitons. Unlike stacked graphene, semiconducting 2D transition metal dichalcogenides (TMDCs) have diffuse interlayer d-orbital overlap. To enhance interlayer electronic coupling in TMDCs, we apply an interlayer-directed E-field, inducing electron-hole dissociation as shown in Fig. 1b. Time-resolved photocurrents show that stacked WSe2 devices shown in Fig. 1a can have both IQE >50% and fast (<60 ps) picosecond electron escape times. Our ultrafast photocurrent rates kinetics give the same E-field-dependent electronic escape and dissociation rates seen from ultrafast optical TA microscopy.[2] To rationalize these fast electronic escape rates, we show the ratio of the electronic rates accurately predicts the actual WSe2 device photocurrent generation efficiency. Lastly, we will show how certain intermolecular twist angle packings of athraditiophene molecular crystals make electron-multiplication by singlet fission of TT states favorable. Singlet fission dynamics are indicated in Fig. 1c by the matching singlet (blue) vs. rising triplet dynamics (red) obtained when the probe polarization aligned along the crystal charge-transfer axis. However, other intermolecular packing angles (at 90o) instead localize and trap excitons as excimers, preventing singlet fission.[3] These interlayer stacked systems collectively demonstrate how remarkably different interlayer electronic states evolve from relatively small changes in interlayer twist angles in van der Waals stacked materials and molecular singlet fission materials. References [1] H. Patel, L. Huang, C.J. Kim, J. Park, M. W. Graham, Stacking Angle-Tunable Photoluminescence from Interlayer Exciton States in Twisted Bilayer Graphene, Nature Comm, 10, 1445 (2019) [2] K. T. Vogt, S.-F. Shi, F. Wang, M. W. Graham, Ultrafast photocurrent and absorption microscopy of few-layer TMD devices isolate rate-limiting dynamics driving fast and efficient photoresponse, J Phys Chem C, 124, 28, 15195–15204 (2020) [3] G. Mayonado, K. T. Vogt, J. Van Schenck, O. Ostroverkhova, M. W. Graham, Packing Morphology-Dependent Singlet Fission in Single Crystal Anthradithiophene Derivatives, OSA Technical Digest: Ultrafast Phenomena, doi.org/10.1364/UP.2020.Th2A.4 (2020) Figure 1

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50

Faye, Bernard, and C. Mulato. "Facteurs de variation des paramètres protéo-énergétiques, enzymatiques et minéraux dans le plasma chez le dromadaire de Djibouti." Revue d’élevage et de médecine vétérinaire des pays tropicaux 44, no. 3 (March 1, 1991): 325–34. http://dx.doi.org/10.19182/remvt.9174.

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Abstract:

L'analyse du plasma de 52 dromadaires (27 femelles adultes, 13 jeunes femelles, 7 mâles adultes et 5 jeunes mâles) en provenance de cinq régions naturelles de Djibouti a concerné 15 paramètres biochimiques. Les valeurs observées tendent à admettre des états de subcarence en oligo-éléments (cuivre : 60, 7 µg/100 ml; zinc : 46,2 µg/100 ml) mais non en calcium (9,5 mg/100 ml), ni en magnésium (2,3 mg/100 ml), bien que dans ce dernier cas les écarts soient grands (1,1-3,9). Par ailleurs, les dromadaires de Djibouti semblent en état de déficit énergétique (63,7 mg/100 ml pour le glucose, 0,025 mmol/l pour le BOH, 0,17 mmol/l pour les acides gras libres), mais le niveau azoté alimentaire serait globalement satisfaisant (urée : 35,9 mg/100 ml, albumine : 32,7 g/l). Les lipides plasmatiques (cholestérol, phospholipides, triglycérides) signent les particularités métaboliques du dromadaire (respectivement 19,5, 22,4 et 26,6 mg/100 ml). Le facteur géographique est prépondérant sur les facteurs zootechniques pour expliquer les différences entre les profils observés. Les caractéristiques des cinq régions sont discutées en relation avec le profil moyen observé sur les animaux.

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