Energy levels, radiative rates, and electron impact excitation rates for transitions in Li-like ions with 12≤Z≤20

We report calculations of energy levels, radiative rates, and electron impact excitation rates for transitions in Li-like ions with 12≤Z≤20. The grasp (general-purpose relativistic atomic structure package) is adopted for calculating energy levels and radiative rates, while for determining the collision strengths and subsequently the excitation rates, the Dirac atomic R-matrix code is used. Oscillator strengths, radiative rates, and line strengths are reported for all E1, E2, M1, and M2 transitions among the lowest 24 levels of the Li-like ions considered. Collision strengths have been averaged over a Maxwellian velocity distribution, and the effective collision strengths obtained are reported over a wide temperature range up to 10^7.4 K. Additionally, lifetimes are also listed for all calculated levels of the ions. Finally, extensive comparisons are made with results available in the literature, as well as with our parallel calculations for all parameters with the Flexible Atomic Code, in order to assess the accuracy of the reported results. 

An effective three-dimensional ordered mesoporous ZnCo2O4 as electrocatalyst for Li-O2 batteries

Three-dimensional ordered mesoporous (3DOM) ZnCo₂O₄ materials have been synthesized via a hard template and used as bifunctional electrocatalysts for rechargeable Li-O₂ batteries. The as-prepared ZnCo₂O₄ nanoparticles possess a high specific surface area of 127.2 m² g^-1 and a spinel crystalline structure. The Li-O₂ battery utilizing 3DOM ZnCo₂O₄ shows a higher specific capacity of 6024 mAh g^-1 than that with pure Ketjen black (KB). Moreover, the ZnCo₂O₄-based electrode enables much enhanced cyclability with a smaller discharge-recharge voltage gap than that of the carbon-only cathode. Such excellent catalytic performance of ZnCo₂O₄ could be associated with its larger surface area and 3D ordered mesoporous structure

Three-dimensional graphene-Co3O4 cathodes for rechargeable Li-O2 batteries

A three-dimensional (3D) graphene-Co₃O₄ electrode was prepared by a two-step method in which graphene was initially deposited on a Ni foam with Co₃O₄ then grown on the resulting graphene structure. Cross-linked Co₃O₄ nanosheets with an open pore structure were fully and vertically distributed throughout the graphene skeleton. The free-standing and binder-free monolithic electrode was used directly as a cathode in a Li-O₂ battery. This composite structure exhibited enhanced performance with a specific capacity of 2453 mA h g^-1 at 0.1 mA cm^-2 and 62 stable cycles with 583 mA h g^-1 (1000 mA h g_carbon^-1). The excellent electrochemical performance is associated with the unique architecture and superior catalytic activity of the 3D electrode. 

Electron-impact excitation of Li to high principal quantum numbers

The time-dependent close-coupling method is used to calculate electron-impact excitation cross sections for the Li(2s)--{\textgreater}Li(nl) and Li(2p)--{\textgreater}Li(nl) transitions at incident energies just above the ionization threshold. The implementation of the time-dependent close-coupling method on a nonuniform lattice allows the study of continuum-coupling effects in excitations to high principal quantum number, i.e., n{\textless}=10. Good agreement is found with R-matrix with pseudostates calculations, which also include continuum-coupling effects, for excitations to low principal quantum number, i.e., n{\textless}=4. Poor agreement is found with standard distorted-wave calculations for excitations to all principal quantum numbers, with differences still at the 50% level for n=10. We are able to give guidance as to the accuracy expected in the n3 extrapolation of nonperturbative close-coupling calculations of low n cross sections and rate coefficients.

Electron-impact ionization of the metastable excited states of Li +

Electron-impact ionization cross sections for the 1s2s 1S and 1s2s 3S metastable states of Li+ are calculated using both perturbative distorted-wave and non-perturbative close-coupling methods. Term-resolved distorted-wave calculations are found to be approximately 15% above term-resolved R-matrix with pseudostates calculations. On the other hand, configuration-average time-dependent close-coupling calculations are found to be in excellent agreement with the configuration-average R-matrix with pseudostates calculations. The non-perturbative R-matrix and close-coupling calculations provide a benchmark for experimental studies of electron-impact ionization of metastable states along the He isoelectronic sequence.

Generalised collisional-radiative model for light elements. A: Data for the Li isonuclear sequence

A first stage collision database is assembled which contains electron-impact effective collision strengths, and ionization and recombination rate coefficients for Li, Li+, and Li2+. The first stage database is constructed using the R-matrix with pseudo-states, time-dependent close-coupling, converged close-coupling, and perturbative distorted-wave methods. A second stage collision database is then assembled which contains generalized collisional-radiative and radiated power loss coefficients. The second stage database is constructed by solution of collisional-radiative equations in the quasi-static equilibrium approximation using the first stage database. Both collision database stages reside in electronic form at the ORNL Controlled Fusion Atomic Data Center and in the ADAS database, and are easily accessed over the worldwide internet. ?? 2006 Elsevier Inc. All rights reserved.

« Li Livre dou Bret », ou Le Roman de Tristan [de LUCE DU GAST].

Commençant par : «... voluntez d'Elinde et landemain quant il fut ajornez... » et finissant par : «... et plairai tant com li mondes durrai, li quex est apelez li Livres dou Bret. Explicit li Livres dou Bret. Amen » . D'après l'épilogue, « HELYE DE BERRON » aurait remanié le travail de LUCE DU GAST, qu'il a divisé en trois livres. Voir l'introduction au livre III, fol. 264. Manque le premier feuillet de chaque livre.

« Li rommans de Godefroy de Buillon et de Salehadin et de tous lez autres roys qui ont esté outre mer jusques a saint Loys qui darrenierement y fu ».

Début : « Si povés vous savoir les sains leus de la terre... — Fin : «... Adonc estoient l'an de l'incarnation Nostre Seigneur mil CCLXI. Explicit les Feiz d'Outremer. Ce livre ci fu complet d'escripture l'an de l'incarnation Nostre Seigneur mil trois cens et trante et VII, le jeudi devant la feste mon seigneur saint Thomas l'apostre devant Noël. » — Nombreuses miniatures. — Au fol. 1, on lit : « Au duc d'Arschot en 1584 ».

Li queste del S. Graal [La quête du Saint-Graal]

Commencement : « A la veille de la Pentecouste quant li compaignon de la Table reonde furent venu a Chamahelot... » — Fin : « ...Et quand Boors ot conté les aventures del S. Graal, teles com il les avoit veu, si furent mises en escript et gardées moult chierement, dont mestres Gautiers Map le traist a faire sen livre del Graal pour l'amour del roy Henri son signour, qui fist l'hystoire translater de latin en franchois. Si s'en taist atant li contes que plus n'en dist des aventures del S. Graal. Amen. — Chius livres fu parescrips le nuit Nostre Dame en mi aoust l'a[n] mil trois cens et LI : si l'escripst Pierars dou Tielt, et enlumina et loia. — Explicit li queste del S. Graal. » Fol. 95 : Annales depuis le commencement du monde jusqu'en 1281. Commencement : « Chi conmencent li an dés le conmencement del monde tres chi qu'en nos temps... » — Fin : « M. CC. LXXIX. Margerite contesse de Flandres et de Hainau moru. Guis ses fieus fu quens. — MCCLXXX. Nicolas pape morut. — MCCLXXXI. Martins fu pape. »

Guiron le Courtois, translaté de latin en françois par Luce du Châtel du Gat. « Cy commence li seconds livres de Guiron le Courtois »

Commencement : « Or dist li contes que li rois Melyadus demoura ou chastel... » — Fin : « ...et encore est communement son nom par toute Engleterre. — Cy fine le tiers et derrenier livre de Guiron le Courtois. »

« Li Abrejance de l'ordre de chevalerie... par... VEGECE FLAIVE », traduction par « JEHAN PRIORAT ».

Commençant par : « Li premiers livres nos ensoingne, Vegeces Flaives le tesmoingne... » et finissant par : « Que Dex le traie à bone fin. Ici mon livre vos defin. Amen. Expliciz li romanz de chevalerie » .

« Li Abregemens de tres noble homme VEGECE des establissemens apartenans à chevalerie », traduction faite en 1284 pour Jean de Brienne Ier, comte d'Eu, par « JEHAN DE MEUN ».

Commençant par : « Li ancien ont esté coustumier de metre en escript les choses qu'ils penssoient qui fussent bonnes à savoir... » et finissant par : «... car li usages et li hanteis de chascun jour trueve plus de l'art en ces choses que l'ancienne doctrine ne nous en a moustré » .