Disclosing Early Excited State Relaxation Events in Prototypical Linear Carbon Chains

One-dimensional (1D) linear nanostructures comprising sp-hybridized carbon atoms, as derivatives of the prototypicalallotropeknown as carbyne, are predicted to possess outstanding mechanical,thermal, and electronic properties. Despite recent advances in theirsynthesis, their chemical and physical properties are still poorlyunderstood. Here, we investigate the photophysics of a prototypicalpolyyne (i.e., 1D chain with alternating single and triple carbonbonds) as the simplest model of finite carbon wire and as a prototypeof sp-carbon-based chains. We perform transient absorptionexperiments with high temporal resolution (<30 fs) on monodispersedhydrogen-capped hexayne H (C C)(6)Hsynthesized by laser ablation in liquid. With the support of computationalstudies based on ground state density functional theory (DFT) andexcited state time-dependent (TD)-DFT calculations, we provide a comprehensivedescription of the excited state relaxation processes at early timesfollowing photoexcitation. We show that the internal conversion froma bright high-energy singlet excited state to a low-lying singletdark state is ultrafast and takes place with a 200 fs time constant,followed by thermalization on the picosecond time scale and decayof the low-energy singlet state with hundreds of picoseconds timeconstant. We also show that the time scale of these processes doesnot depend on the end groups capping the sp-carbonchain. The understanding of the primary photoinduced events in polyynesis of key importance both for fundamental knowledge and for potentialoptoelectronic and light-harvesting applications of low-dimensionalnanostructured carbon-based materials

High-Performance Compression of Multibeam Echosounders Water Column Data

Over the last few decades, multibeam echosounders (MBES) have become the dominant technique to efficiently and accurately map the seafloor. They now allow to collect water column acoustic images along with the bathymetry, which is providing a wealth of new possibilities in oceans exploration. However, water column imagery generates vast amounts of data that poses obvious logistic, economic, and technical challenges. Surprisingly, very few studies have addressed this problem by providing efficient lossless or lossy data compression solutions. Currently, the available options are only lossless, providing low compression ratios at low speeds. In this paper, we adapt a data compression algorithm, the Fully Adaptive Prediction Error Coder (FAPEC), which was created to offer outstanding performance under the strong requirements of space data transmission. We have added to this entropy coder a specific pre-processing stage tailored to theKongsbergMaritime water column file formats. Here, we test it on data acquired with Kongsberg MBES models EM302, EM710, andEM2040.With this bespoke pre-processing, FAPEC provides good lossless compression ratios at high speeds, whereas lossy ratios reach water column file sizes even smaller than bathymetry raw files still with good image quality. We show the advantages over other lossless compression solutions, both in terms of compression ratios and speed.We illustrate the quality of water column images after lossy FAPEC compression, as well as its resilience to datagram errors and its potential for automatic detection of water column targets. We also show the successful integration in ARM microprocessors (like those used by smartphones and also by autonomous underwater vehicles), which provides a real-time solution for MBES water column data compression

Istituzioni artistiche e culturali: gli enti lirici e musicali - Paper

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Globalizzazione e Diritto

Contratti e impresa è un quadrimestrale di analisi critica e ricostruttiva della produzione giurisprudenziale e di valutazione sistematica delle figure giuridiche di creazione legislativa ed extralegislativa. Il suo prevalente terreno è il diritto privato comune: l’area del diritto civile e commerciale entro la quale la giurisprudenza e la modellistica contrattuale svolgono un ruolo preponderante. Il primo numero per il 2005 sviluppa interessanti tematiche relative a: obbligazioni e contratti, contratto di lavoro; società; informatica; responsabilità civile; il giudizio di equità; TV digitale terrestr

Tre modifiche al codice civile nel quarto anniversario dal recepimento della direttiva CEE in tema di clausole abusive

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Il codice di autodisciplina pubblicitaria

Materie: Diritto Pubblico / Diritto Amministrativo / 6. Collegi Professionali e Libere Profession

Trust e stock option

TRUSTS E ATTIVITA' FIDUCIARI

L'Associazione temporanea di imprese

Attività d’impresa Presiede e conclude: Natalino Irt

Danno alla persona per inefficienza della struttura sanitaria. Profili civilistici.

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La disciplina della subfornitura nelle attività produttive

Titolo: La disciplina della subfornitura nelle attività produttive (Legge 18 giugno 1998 n.192) / [Commento a