KevoreeJS: Enabling dynamic software reconfigurations in the Browser

International audienceThe architecture of classic productivity software are moving from a traditional desktop-based software to a client server architecture hosted in the Cloud. In this context, web browsers behave as application containers that allow users to access a variety of Cloud-based applications and services, such as IDEs, Word processors, Music Collection Managers, etc. As a result, a significant part of these software run in the browser and accesses remote services. A lesson learned from development framework used in distributed applications is the success of pluggable architecture pattern as a core architecture concept, i.e., a Software Architecture that promotes the use of Pluggable Module to dynamically plug. Following this trend, this paper discusses the main challenges to create a component-based platform supporting the development of dynamically adaptable single web page applications. This paper also presents an approach called KevoreeJS based on models@runtime to control browser as component platform which address some of these challenges. We validate this work by presenting the design of a dashboard for sensor based system and highlighting the capacity of KevoreeJS to dynamically choose the placement of code on the server or client side and how KevoreeJS can be used to dynamically install or remove running components

Size-Controlled Hapticity Switching in [Ln(C9H9)(C8H8)][Ln(C_{9}H_{9})(C_{8}H_{8})] Sandwiches

Sandwich complexes of lanthanides have recently attracted a considerable amount of interest due to their applications as Single Molecule Magnet (SMM). Herein, a comprehensive series of heteroleptic lanthanide sandwich complexes ligated by the cyclononatetraenyl (Cnt) and the cyclooctatetraenyl (Cot) ligand [Ln(Cot)(Cnt)] (Ln=Tb, Dy, Er, Ho, Yb, and Lu) is reported. The coordination behavior of the Cnt ligand has been investigated along the series and shows different coordination patterns in the solid-state depending on the size of the corresponding lanthanide ion without altering its overall anisotropy. Besides the characterization in the solid state by single-crystal X-ray diffraction and in solution by $^{1}H$NMR, static magnetic studies and ab initio computational studies were performed

Intermediate Valence States in Lanthanide Compounds

International audienceIn memory of Prof. Richard A. Anderse

Reactive Heterobimetallic Complex Combining Divalent Ytterbium and Dimethyl Nickel Fragments

This article presented the synthesis and characterization of original heterobimetallic species combining a divalent lanthanide fragment and a divalent nickel center bridged by the bipyrimidine ligand, a redox-active ligand. X-ray crystal structures were obtained for the Ni monomer (bipym)NiMe2, 1, as well as the heterobimetallic dimer compounds, Cp*2Yb(bipym)NiMe2, 2, along with 1H solution NMR, solid-state magnetic data, and DFT calculations only for 1. The reactivity with CO was investigated on both compounds and the stoichiometric acetone formation is discussed based on kinetic and mechanistic studies. The key role of the lanthanide fragment was demonstrated by the relatively slow CO migratory insertion step, which indicated the stability of the intermediate

Redox activity of a dissymmetric ligand bridging divalent ytter-bium and reactive nickel fragments

International audienceThe reaction of a reactive nickel dimethyl 1 bearing a redox-active, dissymmetric ligand, which is obtained by deprotonation of 2-pyrimidin-2-yl-1H-benzimidazole (Hbimpm) with a divalent lanthanide complex, Cp* 2 Yb(OEt 2), affords an unprecedented, trimeric 2 with C(sp 3)-C(sp 3) bond formation between two ligands in an exo position. Meanwhile, the transient, dimeric species 3 can be isolated with the same ligand coupling fashion, however, with a drastic distorsion angle of the bimpm ligand and reactive NiMe 2 fragment, revealing the possible mechanism of this rearrangement. A much more stable dimeric congener, 5, with an exo ligand coupling, is synthesized in the presence of 18-crown-6, which captures the potassium counter ion. The CC coupling formation between two bimpm ligands results from the effective electron transfer from divalent lanthanide fragments. Without the divalent lanthanide, the reductive coupling occurs on a different carbon of the ligand, nicely showing the modulation of the spin density induced by the presence of the lanthanide ion. The electronic structures of these complexes are investigated by magnetic study (SQUID), indicating a 2 F 7/2 ground state for each ytterbium in all the heterometallics. This work firstly reports ligand coupling reactivity in a redox-active, yet dissymmetric system with divalent organolanthanides, and the reactive nickel moiety can impact the intriguing transition towards a stable homoleptic, trinulear lanthanide species

Cobalt-Catalyzed C(sp2)–CN Bond Activation: Cross-Electrophile Coupling for Biaryl Formation and Mechanistic Insight

International audienceHerein, we report a cross-electrophile coupling of benzonitrile derivatives and aryl halides with a simple cobalt-based catalytic system under mild conditions to form biaryl compounds. Even though the cobalt catalyst is able to activate the C(sp 2)−CN bond alone, the use of the AlMe 3 Lewis acid enhances the reactivity of benzonitriles and improves the cross-selectivity with barely any influence on the functional group compatibility. X-ray structure determination of an original low-valent cobalt species combined with catalytic and stoichiometric reactions reveals a catalytically active cobalt(I) species toward the aryl halide partner. On the other hand, experimental insights, including cyclic voltammetry experiments, suggest the involvement of a cobalt complex of a lower oxidation state to activate the benzonitrile derivative. Finally, density functional theory calculations support the proposed mechanistic cycle involving two low-valent cobalt species of different oxidation states to perform the reaction

Tridentate NNN Ligand Associating Amidoquinoline and Iminophosphorane: Synthesis and Coordination to Pd and Ni Centers

International audienceThe synthesis of a tridentate NNN ligand incorporating an amidoquinoline and an iminophosphorane (L R H, R =Ph, Cy) was carried out. Coordination to Pd II and Ni II precursors gave as expected square planar complexes of general formula [L R MCl]. The most surprising result came from the reaction of L Ph H with [Ni(COD)2] which gave a Ni II-phenyl complex bearing a tridentate amidoquinoline-aminophosphine ligand. This rearrangement would result from a proton transfer assisted by the Ni 0 when stabilized by a phenyl substituent at the phosphorus, as suggested by DFT calculations and complementary experiments. This nickel-phenyl complex formed the corresponding benzoyl complex under a CO atmosphere

Reversible electron transfer in organolanthanide chemistry

International audienceThis article relates the synthesis and characterization of novel heterobimetallic complexes containing a low-valent lanthanide, a tetradentate redox non-innocent ligand, viz. the 4,5,9,10-tetraazaphenanthrene, taphen ligand and transition metal fragments of PdMe 2 and PtMe 2. The experimental results are supported by a theoretical study. Investigation of their reduction properties allowed the formation of isostructural original heterotrimetallic complexes containing two Cp* 2 Yb fragments and the (taphen)MMe 2 (M = Pd and Pt) motifs. These complexes are stable in non-coordinating solvent such as toluene but decompose in coordinating solvents such as thf. Investigation of the internal electron transfer shows that the taphen ligand behaves as a two-electrons reservoir but is capable of transferring back only one electron in thf. This reversible electron(s) transfer is rare in organolanthanide chemistry and show the potential interest of these complexes in reductive chemistry. Additionally, the trinuclear complexes feature odd X-ray crystal structures in which a deviation of symmetry is observed. The latter observation was studied in depth using quantum chemistry calculations highlighting the role of non-covalent weak interactions

Electron Shuttle in N -Heteroaromatic Ni Catalysts for Alkene Isomerization

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The structuring of air source heat pumps' prices in a retrofitting residential buildings market: what did I pay for?

International audienceThe recent European energy proposals for the revision of the Energy Efficiency and the Energy Performance of Buildings Directives emphasize the importance to drive investments into the renovation of building stocks and to stimulate the refurbishment demand. Moreover, the challenge of acquiring data about retrofitting is reasserted because the lack of reliable data is detrimental to the perception of costeffectiveness. Especially it is well known that refurbishment prices are, according to various papers, subject to large uncertainty and can sometimes be controversial even if public subsidies are available. In this paper, we evaluate the main determinants of prices. Their structuring is a complex phenomenon blending technical, economical and organizational sides. For such purpose, we analyzed hundreds of invoices concerning the installation of heat pumps in existing buildings. In order to model the influence of the different variables on the upfront cost paid by the households, we developed general linear statistical models (ANCOVA) blending qualitative and quantitative variables. The variables taken into account are: • Technical: living area, type of building (multi or single fam ily), coefficient of performance, installed power; • and economic: company description (number of employees, main activity and sales network), average household's income linked to location, brand of equipment installed. Our results confirm the importance of economic variables (such as brand or sales network) beside the technical variables in the explanation of prices. Our results also quantify the relative role of each variable. Half of the prices' variation is explained by the models and it is a huge step in the understanding of retrofit prices in order to better orientate the public subsidies