Institution
Paul Sabatier University
Education•Toulouse, France•
About: Paul Sabatier University is a education organization based out in Toulouse, France. It is known for research contribution in the topics: Population & Catalysis. The organization has 15431 authors who have published 23386 publications receiving 858364 citations.
Topics: Population, Catalysis, Context (language use), Adipose tissue, Electron
Papers published on a yearly basis
Papers
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TL;DR: This mini-review will aim to provide an overview of recent efforts aimed at understanding and controlling dynamic cross-linking reactions within vitrimers, and how directing this chemical reactivity can be used as a handle to steer material properties.
Abstract: The development of more sustainable materials with a prolonged useful lifetime is a key requirement for a transition towards a more circular economy. However, polymer materials that are long-lasting and highly durable also tend to have a limited application potential for re-use. This is because such materials derive their durable properties from a high degree of chemical connectivity, resulting in rigid meshes or networks of polymer chains with a high intrinsic resistance to deformation. Once such polymers are fully synthesised, thermal (re)processing becomes hard (or impossible) to achieve without damaging the degree of chemical connectivity, and most recycling options quickly lead to a drop or even loss of material properties. In this context, both academic and industrial researchers have taken a keen interest in materials design that combines high degrees of chemical connectivity with an improved thermal (re)processability, mediated through a dynamic exchange reaction of covalent bonds. In particular vitrimer materials offer a promising concept because they completely maintain their degree of chemical connectivity at all times, yet can show a clear thermally driven plasticity and liquid behavior, enabled through rapid bond rearrangement reactions within the network. In the past decade, many suitable dynamic covalent chemistries were developed to create vitrimer materials, and are now applicable to a wide range of polymer matrices. The material properties of vitrimers, however, do not solely rely on the chemical structure of the polymer matrix, but also on the chemical reactivity of the dynamic bonds. Thus, chemical reactivity considerations become an integral part of material design, which has to take into account for example catalytic and cross-reactivity effects. This mini-review will aim to provide an overview of recent efforts aimed at understanding and controlling dynamic cross-linking reactions within vitrimers, and how directing this chemical reactivity can be used as a handle to steer material properties. Hence, it is shown how a focus on a fundamental chemical understanding can pave the way towards new sustainable materials and applications.
225 citations
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TL;DR: The density of states in Gaussian ensembles whose eigenvalues are restricted to lie in the interval [zeta1,zeta2] is obtained, thus generalizing the celebrated Wigner semi-circle law to these restricted ensemble.
Abstract: We compute exact asymptotic results for the probability of the occurrence of large deviations of the largest (smallest) eigenvalue of random matrices belonging to the Gaussian orthogonal, unitary, and symplectic ensembles. In particular, we show that the probability that all the eigenvalues of an $(N\ifmmode\times\else\texttimes\fi{}N)$ random matrix are positive (negative) decreases for large $N$ as $\ensuremath{\sim}\text{exp}\text{ }[\ensuremath{-}\ensuremath{\beta}\ensuremath{\theta}(0){N}^{2}]$ where the Dyson index $\ensuremath{\beta}$ characterizes the ensemble and the exponent $\ensuremath{\theta}(0)=(\text{ln}\text{ }3)/4=0.274653\dots{}$ is universal. We compute the probability that the eigenvalues lie in the interval $[{\ensuremath{\zeta}}_{1},{\ensuremath{\zeta}}_{2}]$ which allows us to calculate the joint probability distribution of the minimum and the maximum eigenvalue. As a by-product, we also obtain exactly the average density of states in Gaussian ensembles whose eigenvalues are restricted to lie in the interval $[{\ensuremath{\zeta}}_{1},{\ensuremath{\zeta}}_{2}]$, thus generalizing the celebrated Wigner semi-circle law to these restricted ensembles. It is found that the density of states generically exhibits an inverse square-root singularity at the location of the barriers. These results are confirmed by numerical simulations. Some of the results presented in detail here were announced in a previous paper [D. S. Dean and S. N. Majumdar, Phys. Rev. Lett. 97, 160201 (2006)].
225 citations
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TL;DR: In this article, the steady state dissolution rates of a K-rich feldspar (K081Na015Ba003Al105Si296O8) were measured as a function of chemical affinity and aqueous Si and Al concentration in solutions containing 5 × 10−3 m total K using a titanium mixed flow reactor at a temperature of 150°C and pH of 90.
224 citations
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University of Bergen1, University of Copenhagen2, National Institutes of Health3, National University of Ireland, Galway4, University of Turin5, Ghent University6, University of Siena7, Istanbul University8, University of Southern Denmark9, University of Hamburg10, University of Edinburgh11, Karolinska Institutet12, Paul Sabatier University13
TL;DR: Overweight prevalence in youth remained high across the countries examined and the primary factors linked to overweight were breakfast consumption and physical activity.
Abstract: Objectives:
To examine overweight prevalence and its association with demographic and lifestyle factors in 11–15 year olds in the HBSC 2005–2006 survey.
224 citations
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TL;DR: This work presents the functional traits that have already been used to assess the key functions played by fish and highlights how a trait-based framework could provide valuable insights on the mechanistic links between global changes, functional diversity of fish assemblages, and ecosystem services.
Abstract: Fish communities face increasing anthropogenic pressures in freshwater and marine ecosystems that modify their biodiversity and threaten the services they supply to human populations. To address these issues, studies have been increasingly focusing on functions of fish that are linked to their main ecological roles in aquatic ecosystems. Fish are indeed known to control other organisms through predation, mediate nutrient fluxes, and can act as ecosystem engineers. Here for each of the key functions played by fish, we present the functional traits that have already been used to assess them. We include traits measurable from observations on living individuals, morphological features measured on preserved organisms or traits categorized using information from the literature, and we discuss their respective advantages and limitations. We then list future research directions to foster a more complete functional approach for fish ecology that needs to incorporate functional traits describing, food provisioning and cultural services while accounting more frequently for intraspecific variability. Finally, we highlight ecological and evolutionary questions that could be addressed using meta-analyses of large trait databases, and how a trait-based framework could provide valuable insights on the mechanistic links between global changes, functional diversity of fish assemblages, and ecosystem services.
224 citations
Authors
Showing all 15486 results
Name | H-index | Papers | Citations |
---|---|---|---|
Yury Gogotsi | 171 | 956 | 144520 |
Tobin J. Marks | 159 | 1621 | 111604 |
L. Montier | 138 | 403 | 97094 |
Jean-Paul Kneib | 138 | 805 | 89287 |
Olivier Forni | 137 | 548 | 95819 |
J. Aumont | 131 | 299 | 95006 |
Julian I. Schroeder | 120 | 315 | 50323 |
Bruno Vellas | 118 | 1011 | 70667 |
Christopher G. Goetz | 116 | 651 | 59510 |
Didier Dubois | 113 | 742 | 54741 |
Alain Dufresne | 111 | 358 | 45904 |
Henri Prade | 108 | 917 | 54583 |
Louis Bernatchez | 106 | 568 | 35682 |
Walter Wahli | 105 | 365 | 49372 |
Patrice D. Cani | 100 | 370 | 49523 |