786 research outputs found
Synthesis and characterization of advanced materials for Li-ion batteries :\ud 1. Si/RGO nanocomposite anodes.\ud 2. V2O5 gel cathodes.
No full textLithium-ion batteries represent the state-of-the-art of electrochemical energy storage. However, with the advance of microelectronic technology for portable devices and the progressive introduction into the automotive market of Electrical Vehicles (EVs.), a breakthrough in Li-ion materials is needed to overcome known issues related to cost, higher energy densities, safety and cycle life. Moreover, steps forward are also needed from a sustainability point of view, in order to reduce both costs and environmental impact during battery manufacturing.\ud
On the anode side, research in next-generation materials, capable of replacing the industry-standard graphite, are now underway. In this PhD thesis, a novel high capacity Silicon/Reduced Graphene Oxide (Si/RGO) nanocomposite has been synthesized, thoroughly characterized and evaluated under an electrochemical point of view. The electrode preparation has been optimized using an alternative binder and eco-friendly solvent like ethanol. The composite shows a good stability and capacity retention over prolonged cycling.\ud
On the cathode side, next-generation materials should have higher capacities in order to increase the energy density of the future batteries. In this PhD thesis, Vanadium Pentoxide (V2O5) - has been studied both in its amorphous (aerogel) and crystalline form as next generation Li-ion cathode materials. Also in this case materials were prepared, characterized and electrochemically tested. A green and eco-friendly approach during electrode processing was used also in this case.\ud
The data resulting from this PhD thesis were subject of the following publications and proceedings of congresses:\ud
- F. Maroni, R. Raccichini, A. Birrozzi, G. Carbonari, R. Tossici, F. Croce, R. Marassi, F. Nobili Graphene/silicon nanocomposite anode with enhanced electrochemical stability for lithium-ion battery applications, J. Power Sources, 2014; Vol. 269; 873 – 882. doi:10.1016/j.jpowsour.2014.07.064\ud
- A. Moretti, F. Maroni, F. Nobili, S. Passerini, V2O5 electrodes with extended cycling ability and improved rate performance using polyacrylic acid as binder, J. Power Sources, 2014, In Press. doi : 10.1016/j.jpowsour.2014.09.150\ud
- A. Moretti, F. Maroni, I. Osada, F. Nobili, S. Passerini, V2O5 aerogel as a versatile cathode material for lithium and sodium batteries, ChemElectroChem, 2014, In Press.\ud
- F. Nobili, F. Maroni, R. Raccichini, R. Tossici, R. Marassi, A Silicon/Graphene Composite Anode for High-Efficiency Lithium Batteries, 17th International Meeting on Lithium Batteries, June 10/14 2014, Cernobbio (CO) Italy, Abstract #361.\ud
- F. Nobili, F. Maroni, R. Raccichini, R. Tossici, R. Marassi, Graphene/Silicon nanocomposite anode with enhanced electrochemical stability for Li-ion battery applications, Green Lion European Project Workshop, October 28-29 2014, Ulm, Germany Abstract #20.\ud
- Si/RGO nanocomposite development was carried out within the ENEA project “Ricerca di materiali anodici per batterie litio ione operanti in elettroliti organici convenzionali di più elevata energia rispetto a quelle sul mercato” and reported in the following documents:\ud
- R. Marassi, F. Nobili, R. Tossici, M. Marinaro, A. Birrozzi, R. Raccichini, RdS 2012\ud
- A. Birrozzi, F. Maroni, G. Carbonari, R. Tossici, F. Nobili, R. Marassi, RdS 201
Buffering volume changes of Si nanocomposite anodes
No full textThe massive development of Li-ion technology has allowed for massive spreading of portable electronics, as well as for a progressive development of electrical vehicles (EV) with higher driving range. Despite this, the ever-increasing demand in energy density requests for a breakthrough in Li-storage materials. In this context, anode materials alternative to conventional graphite, with improved capacity, have been investigated for several years. Among these, Si plays a special role because of its extremely high theoretical capacity (4200 mAh g-1 corresponding to the formation of a Li22Si4 alloy). Nevertheless, the volume changes of about 300% associated with the alloying/dealloying processes represent a severe limitation to the electrode reversibility, so that actions aimed at counteracting this drawback are needed for the development of durable Si anodes.
The electrochemical behaviour of nanocomposite materials, based on commercial Si powder of about 100 nm size in which the volume changes are buffered by dispersing matrixes such as reduced graphene oxide (RGO) or transition metal oxides, is here presented. The electrodes and cells performances, in terms of specific capacity and durability, are optimized by the use of tailored binders and electrolyte formulations. A rationale of the improved behaviour is explored by applying several morphological, structural and electrochemical investigation techniques, with a special focus on electrode/electrolyte interfacial properties.
References:
1. M.N. Obrovac, L. Chistensen, Electrochem. Solid State Lett. 7 (2004) A93.
2. F. Maroni, R. Raccichini, A. Birrozzi, G. Carbonari, R. Tossici, F. Croce, R. Marassi, F. Nobili, J. Power Sources 269 (2014) 873
Giancarlo maroni, Gabriele d'Annunzio e gli artisti per il Vittoriale: un breve itinerario all'interno della "Santa Fabbrica"
No full textContributo nel catalogo della mostra "L’architetto del lago. Giancarlo Maroni e il Garda" presso il Museo Civico di Riva del Garda (TN
Quadratic decomposition of Laguerre polynomials via lowering operators
No full textA Laguerre polynomial sequence of parameter ?/2 was previously characterized in a recent work [Ana F. Loureiro and P. Maroni (2008) [28]] as an orthogonal F?-Appell sequence, where F? represents a lowering (or annihilating) operator depending on the complex parameter ???2n for any integer n?0. Here, we proceed to the quadratic decomposition of an F?-Appell sequence, and we conclude that the four sequences obtained by this approach are also Appell but with respect to another lowering operator consisting of a Fourth-order linear differential operator G?,?, where ? is either 1 or ?1. Therefore, we introduce and develop the concept of the G?,?-Appell sequences and we prove that they cannot be orthogonal. Finally, the quadratic decomposition of the non-symmetric sequence of Laguerre polynomials (with parameter ?/2) is fully accomplished
Surgical management of hepatocellular carcinoma — Western versus eastern attitude
No full textHepatocellular carcinoma (HCC) is the most common liver tumour and represents a significant health burden. The different characteristics of the disease in the various parts of the world, as much as economic and social features, explain only partially the great diversity in the treatment options offered to patients in different countries. The most apparent contrast in term of tumour management is between the western and eastern world. Striking differences involve not only the attitude towards indications for liver transplantation or liver resection but also the surgical techniques adopted. Although remarkable signs of progress have been achieved in surgical and pharmacological fields, univocal guidelines are yet lacking, preventing effective comparisons between retrospective studies and clinical trials. This review aims to analyse and compare some of the most relevant and essential traits of the eastern and western therapeutic strategy against HCC
Risk assessment and management of occupational exposure to pesticides in agriculture
No full textNearly 50% of the world labour force is employed in agriculture. Over the last 50 years, agriculture has deeply
changed with a massive utilisation of pesticides and fertilisers to enhance crop protection and production, food quality
and food preservation. Pesticides are also increasingly employed for public health purposes and for domestic use.
Pesticide are unique chemicals as they are intrinsically toxic for several biological targets, are deliberately spread into
the environment, and their toxicity has a limited species selectivity. Pesticide toxicity depends on the compound
family and is generally greater for the older compounds; in humans, they are responsible for acute poisonings as well
as for long term health effects, including cancer and adverse effects on reproduction. Due to their intrinsic toxicity,
in most countries a specific and complex legislation prescribes a thorough risk assessment process for pesticides prior to
their entrance to the market (pre-marketing risk assessment). The post-marketing risk assessment takes place during
the use of pesticides and aims at assessing the risk for exposed operators. The results of the risk assessment are the base
for the health surveillance of exposed workers. Occupational exposure to pesticides in agriculture concerns product
distributors, mixers and loaders, applicators, bystanders, and rural workers re-entering the fields shortly after treatment.
Assessing and managing the occupational health risks posed by the use of pesticides in agriculture is a complex
but essential task for occupational health specialists and toxicologists. In spite of the economic and social importance
of agriculture, the health protection of agricultural workforce has been overlooked for too many years, causing an
heavy tribute paid in terms of avoidable diseases, human sufferance, and economic losses. Particularly in the developing
countries, where agricultural work is one of the predominant job, a sustainable model of development calls for
more attention to occupational risks in agriculture. The experience of many countries has shown that prevention of
health risk caused by pesticides is technically feasible and economically rewarding for the individuals and the whole
community. A proper risk assessment and management of pesticide use is an essential component of this preventative
strategy
Letter to William F. M. Arny from Maroni S. Bunker
No full textLetter of application dated April 29, 1863 to William Frederick Milton Arny, Governor of New Mexico, from Maroni S. Bunker, Marvin S. Bunker?, Albuquerque, for a military commission in the Volunteer vervices of New Mexico. He noted his long service career and those recommending him. Civil War. HL introduction page overlaid by document. Letter in English, handwritten, 2pp/fr
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