4 resultados para Running coupling
em AMS Tesi di Laurea - Alm@DL - Università di Bologna
Resumo:
A growing interest towards new sources of energy has led in recent years to the development of a new generation of catalysts for alcohol dehydrogenative coupling (ADC). This green, atom-efficient reaction is capable of turning alcohol derivatives into higher value and chemically more attractive ester molecules, and it finds interesting applications in the transformation of the large variety of products deriving from biomass. In the present work, a new series of ruthenium-PNP pincer complexes are investigated for the transformation of 1-butanol, one of the most challenging substrates for this type of reactions, into butyl butyrate, a short-chain symmetrical ester widely used in flavor industries. Since the reaction kinetics depends on hydrogen diffusion, the study aimed at identifying proper reactor type and right catalyst concentration to avoid mass transfer interferences and to get dependable data. A comparison between catalytic activities and productivities has been made to establish the role of the different ligands bonded both to the PNP binder and to the ruthenium metal center, and hence to find the best catalyst for this type of reaction.
Resumo:
Our generation of computational scientists is living in an exciting time: not only do we get to pioneer important algorithms and computations, we also get to set standards on how computational research should be conducted and published. From Euclid’s reasoning and Galileo’s experiments, it took hundreds of years for the theoretical and experimental branches of science to develop standards for publication and peer review. Computational science, rightly regarded as the third branch, can walk the same road much faster. The success and credibility of science are anchored in the willingness of scientists to expose their ideas and results to independent testing and replication by other scientists. This requires the complete and open exchange of data, procedures and materials. The idea of a “replication by other scientists” in reference to computations is more commonly known as “reproducible research”. In this context the journal “EAI Endorsed Transactions on Performance & Modeling, Simulation, Experimentation and Complex Systems” had the exciting and original idea to make the scientist able to submit simultaneously the article and the computation materials (software, data, etc..) which has been used to produce the contents of the article. The goal of this procedure is to allow the scientific community to verify the content of the paper, reproducing it in the platform independently from the OS chosen, confirm or invalidate it and especially allow its reuse to reproduce new results. This procedure is therefore not helpful if there is no minimum methodological support. In fact, the raw data sets and the software are difficult to exploit without the logic that guided their use or their production. This led us to think that in addition to the data sets and the software, an additional element must be provided: the workflow that relies all of them.
Resumo:
L'elaborato si impegna ad esporre i risultati derivanti da una revisione estensiva della letteratura riguardante le pratiche di misurazione della sostenibilità in azienda. Si è scelto un approccio al problema di impostazione bibliometrico, consistente in analisi statistiche di dati bibliografici ricavabili osservando le relazioni tra documenti. Si sono utilizzati strumenti di clustering per categorizzare la letteratura ed individuare le aree di maggior interesse potenziali per aziende che desiderino investire con successo nella sostenibilità. Come risultato, si è ottenuta una chiara identificazione delle principali tematiche che devono essere tenute in considerazione nell’affrontare valutazioni relative alla misurazione e valorizzazione dei concetti di sostenibilità e impatto ambientale in ambito aziendale. Il presente lavoro si presenta inoltre come guida metodologica per un approccio quantitativo alla revisione della letteratura, adattabile ed applicabile in maniera iterativa per un continuo monitoraggio del tema o per indagini in altri ambiti. Questa tesi si pone dunque come base per ricerche e analisi successive finalizzate alla comprensione della letteratura.