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The Apollon 10 PW laser: experimental and theoretical investigation of the temporal characteristics

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High Power Laser Science and Engineering 2016年第3期4卷 127-133页

作者： D.N.Papadopoulos J.P.Zou C.Le Blanc G.Chriaux P.Georges F.Druon G.Mennerat P.Ramirez L.Martin A.Frneaux A.Beluze N.Lebas P.Monot F.Mathieu P.Audebert Laboratoire pour l'Utilisation des Lasers Intenses CNRSEcole Polytechnique Laboratoire Charles Fabry UMR 8501 Institut d'OptiqueCNRS Univ Paris Sud CEA Iramis SPAM

The objective of the Apollon 10 PW project is the generation of 10 PW peak power pulses of 15 fs at 1 shot min^(-1). In this paper a brief update on the current status of the Apollon project is presented, followed by a more detailed presentation of our experimental and theoretical investigations of the temporal characteristics of the laser. More specifically the design considerations as well as the technological and physical limitations to achieve the intended pulse duration and contrast are discussed.

关键词： high intensity lasers spatiotemporal effects ultrafast lasers

Highly sensitive ZnO nanoparticles-loaded In2O3 hollow microsphere for detecting ppb-level NO2 at low working temperature

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Progress in Natural Science:Materials International 2020年第4期30卷 469-476页

作者： Chao Zhang Dongjin Sun Yuchun Huan Kaidi Wu Hanlin Liao College of Mechanical Engineering Yangzhou University ICB umr 6303 CNRS Univ.Bourgogne Franche-Comté

This paper presents a NO2sensor operating at low temperature, which was fabricated by ZnO nanoparticlesloaded In2O3hollow microspheres composites. SEM, XRD, XPS and HRTEM were executed to determine the morphology and microstructure of ZnO–In2O3. The sensing performance of pure In2O3and ZnO–In2O3composite sensors was tested. The NO2sensing properties of the composite were greatly improved in contrast with the pure In2O3sensor at the optimized operating temperature（75 °C）. ZnO–In2O3composite sensor exhibited an obviously higher response（805.2 for 100 ppb NO2） than that of the pure In2O3sensor（14 for 100 ppb NO2）. In particular, the response/recovery rate of ZnO–In2O3composite sensor was greatly improved in contrast with the pure In2O3sensor. The n-n heterojunctions created at ZnO–In2O3interfaces improved the sensing performance.

关键词： ZnO-In 2 O 3 Hollow microspheres Gas sensor NO 2 sensor Low operating temperature

Gate length dependent transport properties of in-plane core-shell nanowires with raised contacts

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Nano Research 2020年第1期13卷 61-66页

作者： Alexandre Bucamp Christophe Coinon David Troadec Sylvie Lepilliet Gilles Patriarche Xavier Wallart Ludovic Desplanque Univ.Lille CNRSCentrale LilleYncréa ISENUniv.Polytechnique Hauts-de-FranceUMR 8520-IEMNF-59000LilleFrance C2N-umr 9001 cnrs UniversitéParis-Sud-UniversitéParis-Saclay91120PalaiseauFrance

Three-dimensional(3D)nanoscale crystal shaping has become essential for the precise design of advanced electronic and quantum devices based on electrically gated *** this context,Ⅲ-Ⅴ semiconductor-based nanowires with low electron effective mass and strong spin-orbit coupling are particularly investigated because of their exceptional quantum transport properties and the good electrostatic control they *** the main challenges involved in the processing of these nanodevices are(i)the management of the gate stack which requires ex-situ passivation treatment to reduce the density of traps at the oxide/semiconductor interface,(ii)the ability to get good ohmic contacts for source and drain electrodes and(iii)the scalability and reliability of the process for the fabrication of complex architectures based on nanowire *** this paper,we show that selective area molecular beam epitaxy of in-plane InGaAs/InP core-shell nanowires with raised heavily doped source and drain contacts can address these different *** characterization of the devices down to 4 K reveals the positive impact of the InP shell on the gate electrostatic control and effective electron *** comparable to the best reported values for In(Ga)As nanostructures grown on InP,this latter is severely reduced for sub-100 nm channel highlighting remaining issue to reach the ballistic regime.

关键词： molecular beam epitaxy core-shell nanowire selective area growth effective electron mobility

Some Notes on Large Deviations of Markov Processes

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Acta Mathematica Sinica,English Series 2000年第3期16卷 369-394页

作者： Liming Wu Laboratoire de Mathématiques Appliquées,cnrs-umr 6620 UniversitéBlaise Pascal,63177,A UBIERE,France and Department of Mathematics,Wuhan University Wuhan,430072 P.R China Laboratoire de Mathématiques Appliquées CNRS-UMR 6620 Université Blaise Pascal AUBIERRE France

In this paper we shall characterize the large deviation principles(abbreviated to LDP) of Donsker-Varadhan of a Markov process both for the weak convergence topology and for theτ- topology,by means of a hyper-exponential recurrence property.A Lyapunov criterion for this type of recurrence property is *** results are applied to countable Markov chains,unidimensional diffusions,elliptic or hypoelliptic diffusions on Riemannian *** counter-examples are equally presented.

关键词： Large deviations hyper-exponential recurrence T-topology uniformly integrable operators

Combining Metabolomics and Gene Expression Analysis Reveals that Propionyl- and Butyryl- Carnitines Are Involved in Late Stages of Arbuscular Mycorrhizal Symbiosis

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Molecular Plant 2014年第3期7卷 554-566页

作者： Jerome Laparre Universite de Toulouse UPS UMR 5546 Laboratoire de Recherche en Sciences Vegetales BP 42617 F-31326 Castanet-Tolosan France cnrs UMR 5546 BP 42617 F-31326 Castanet-Tolosan France Universite de Toulouse INSA UPS INP LISBP Toulouse France INRA UMR792 Ingenierie des Systemes Biologiques et des Procedes Toulouse France CNRS INRA Toulouse France cnrs UMR5504 Toulouse France

The arbuscular mycorrhizal （AM） symbiosis is a widespread mutualistic association between soil fungi （Glomeromycota） and the roots of most plant species. AM fungi are obligate biotrophs whose development is partially under the control of their plant host. We explored the possibility to combine metabolomic and transcriptomic approaches to find putative mycorrhiza-associated metabolites regulating AM fungal development. Methanol extracts of Medicago truncatula roots colonized or not with the AM fungus Rhizophagus irregularis were analyzed and compared by ultra- high-performance liquid chromatography （UHPLC）, high-resolution mass spectrometry （Q-TOF）, and multivariate statisti- cal discrimination. We detected 71 mycorrhiza-associated analytes exclusively present or at least 10-fold more abundant in mycorrhizal roots. To identify among these analytes those that could regulate AM fungal development, we fraction- ated by preparative and semi-preparative HPLC the mycorrhizal and non-mycorrhizal root extracts and established how the 71 analytes were distributed among the fractions. Then we tested the activity of the fractions on germinating spores of R. irregularis by quantifying the expression of 96 genes known for their diverse in planta expression patterns. These investigations reveal that propionyl- and butyryl-carnitines accumulated in mycorrhizal roots. The results suggest that these two molecules regulate fungal gene expression in planta and represent interesting candidates for further biologi- cal characterization.

关键词： metabolomics AM fungi symbiosis plant metabolites carnitines transcriptomic screening.

The allometry of number of feathers in birds changes seasonally

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Chinese Birds 2015年第1期6卷 1-5页

作者： Anders Pape Mller Laboratoire d’Ecologie Systématique et Evolution CNRS UMR 8079Université Paris-Sud

Background: Feathers are a defining feature of birds with multiple functions such as flight, insulation, protection against predation and signaling. Feathers are lost during the annual molt while the rate of such loss at other times of the year and its fitness consequences remain poorly ***: I used information on the number and the mass of feathers for 160 individuals belonging to 85 species of birds in general linear mixed models to analyze allometry of feathers and to investigate possible factors explaining variation in the number of feathers. A phylogenetic effect was assessed by quantifying the random effect of ***: The total mass of feathers increased isometrically with body mass, while the total number of feathers and the mean mass of feathers showed negative allometry. Negative allometry implied that small-sized species had relatively many small feathers. There was a negative association between the number of feathers and migration distance. The total number of feathers initially increased during fall and winter, consistent with individuals growing more feathers later during the year or with individuals with fewer feathers selectively disappearing from the population. In contrast, the number of feathers decreased from winter through spring and ***: These findings suggest that thermoregulation has affected the evolution of the number and the size of feathers, there is selection against feather loss, and that the number of feathers varies across seasons.

关键词： Feather loss Molt Number of feathers Predation Thermoregulation

The exercise-cognition relationship:A virtuous circle

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Journal of Sport and Health Science 2019年第4期8卷 339-347页

作者： Michel Audiffren Nathalie André Research Institute on Cognition and Learning (umr cnrs 7295) University of PoitiersSport Sciences Faculty

Exercise and health psychology have generated 2 sets of empirical studies guided by separate theory-driven *** first axis focuses on the causal relationship between chronic exercise and cognition and,more particularly,high-level cognitive functions such as executive functions(EFs).The second axis examines factors influencing the adherence process to physical activity(PA).Research conducted during the past decade shows that these 2 topics are closely linked,with EFs and effortful control playing a pivotal role in the bidirectional relationship linking PA and mental/brain *** present article supports the idea that an individual engaged in the regular practice of effortful PA initiates a virtuous circle linking PA and effortful control in a bidirectional *** the one hand,chronic exercise leads to an improvement of EFs and effortful *** the other hand,gains in EFs and effortful control effectiveness lead to a reciprocal facilitation of the maintenance of PA over *** limitations and perspectives to this effort hypothesis are proposed in the last part of the article.

关键词： Adherence Effort Executive functions Physical activity Salience network

Shape Controllable Preparation of Submicronic Cadmium Tetrazole-Based Metal-Organic Frameworks via Solvothermal or Microwave-Assisted Methods and Their Photocatalytic Studies

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Chinese Journal of Chemistry 2017年第2期35卷 209-216页

作者： Arti Chouhan Guillaume Pilet Stephane Daniele Ashutosh Pandey Department of Chemistry MNNIT Allahabad Allahabad 211004 India LMI UMR CNRS 5615 University Claude Bernard-Lyon 1 69622 Villeurbanne cedex France IRCELYON UMR CNRS 5256 University Claude Bernard-Lyon 1 69626 Villeurbanne cedex France

The paper describes the experiments conducted to create shape controllable preparations of submicronic cad- mium tetrazole-based MOFs. In order to prepare the submicron sized blocks and tubes of bis[5-（2-pyridyltetrazo- lato）]diaquacadmium（II） [（2-PTZ）2Cd（H20）2] MOFs both solvothermal and microwave augmented reaction proce- dures have been followed. Cadmium nitrate tetrahydrate, cyanopyridine and sodium azide were used as reactants in both the conditions without any surfactants or modulators. Subsequently, IR spectroscopy and single-crystal X-ray crystallographic studies were performed on the prepared MOFs. Examinations using scanning electron microscopy and X-ray powder diffraction of the products made by the microwave method showed formation of bundles of reg- ular submicrotubes, as opposed to the submicron-sized irregular blocks of the Cd-MOF obtained through the sol- vothermal method. The fluorescence peak of the sub-microtube MOF was found at 460 nm while the irregu- lar-blocks emitted at 442 nm indicating a red shift for the former. In addition, the relative intensity of the peak at 460 nm was higher in the former, indicating a decrease in the crystallite size. Band gaps of the MOFs calculated by using the Tauc plots were 2.87 and 2.73 eV, respectively. Their photocatalytic performances using methylene blue under UV-vis irradiation have been investigated.

关键词： cadmium microwave synthesis solvothermal synthesis submicrotube photocatalysis

Surface morphology-optical properties relationship in thermochromic VO_(2) thin films obtained by air oxidation of vanadium nitride

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Journal of Materiomics 2021年第4期7卷 657-664页

作者： A.C.García-Wong D.Pilloud S.Bruyere D.Mangin S.Migot J.F.Pierson F.Capon Institut Jean Lamour(umr cnrs 7198) Universite de Lorraine54000NancyFrance

In this paper,vanadium nitride(VN)thin films have been deposited on Al substrates by reactive magnetron *** VO_(2) films have been obtained by air oxidation of VN samples performed at three temperatures(450,525 and 550℃)at various durations(lower than 50 min).X-ray diffraction and Raman spectrometry of the VN oxidized films indicate that VO_(2) and V2O5 are the only phases produced during the oxidation *** dioxide is the first oxide *** coexists with VN in a long period at 450℃ or suddenly disappears at 525 and 550℃.Whatever the temperature,V2O5 is exclusively detected after the total oxidation of *** oxide is detrimental to the thermochromic performance of *** emissivity-switching properties of the oxidized films were analyzed by infrared camera in the 7.5e13 mm *** comparison among all the samples exhibiting a thermochromic behavior shows that the maximum emissivity switch is independent of the oxidation temperature and the surface morphology of the *** results could open a new strategy in the investigation of VN oxidation as a method to obtain VO_(2),along with an insight into the correlation between surface morphology and optical properties.

关键词： Vanadium dioxide Vanadium nitride Thermochromism Optical properties Air oxidation