Search results for " carbon"
showing 10 items of 1750 documents
Catalizzatori a base di nanocorni di carbonio-liquidi ionici per la conversione della CO2
2017
Nel presente lavoro sono stati impiegati nanocorni di carbonio (CNHs) come piattaforma catalitica per il design di nuovi materiali ibridi a base di sali di imidazolio per la conversione della CO2 in carbonati ciclici. A tale scopo sono stati preparati una serie di catalizzatori eterogenei mediante una procedura sintetica one-pot basata sulla polimerizzazione radicalica di vari sali di bis vinilimidazolio in presenza di nanocorni di carbonio. I suddetti materiali sono stati caratterizzati e testati con successo per la reazione di fissazione della CO2 in epossidi (Figura 1). Figura 1 Conversione della CO2 catalizzata da liquidi ionici supportati su CNHs Le performances catalitiche, valutate i…
Nanocompositi a base polimerica a durabilità modulata mediante il controllo delle proprietà antiossidanti di nanostrutture carboniose
Fibre a base di poliammide e nanotubi di carbonio: proprietà e morfologia
2012
Multifunctional hybrid nanocomposites based on carbon nanotubes and chemically modified graphene
2013
La Tesis trata del desarrollo de materiales híbridos multifuncionales basados en nanotubos de carbono y grafeno con interés en magnetismo molecular y electrónica molecular This Thesis deals with the chemistry and development of new hybrid multifunctional systems based on carbon nanotubes (CNTs) and graphene (G). To introduce both types of carbon nanoforms a brief historical overview of these systems has been briefly given at the Preface. Next and prior to the presentation of the results, two introductory chapters in which the principal aspects of the synthesis, properties and applications of carbon nanotubes (chapter 1) and graphene (chapter 2) are given. The results have been divided in th…
Can differences in microbial abundances help explain enhanced N2O emissions in a permanent grassland under elevated atmospheric CO2?
2011
El CO2 como disolvente y como reactivo
2016
Existen numerosas ventajas asociada con el uso de CO2 , tanto como disolvente que como reactivo, y todas se pueden resumir en cuatro categorías generales: beneficios ambiental, beneficios de salud y seguridad, beneficios en el procedimiento y beneficios químicos. Los procesos que implican el CO2 como disolvente no aumentaría las emisiones de CO2, más bien proporcionaría una oportunidad para el reciclaje de CO2 residual. Además, los esfuerzos para secuestrar el CO2 producido de los gases de combustión de las distintas industrias están rápidamente incrementando. En este contexto se ha decidido estudiar la reacción de hidrogenación de nitrilos utilizando el CO2sc como medio de reacción y CO2 a…
Direct Visualization of Molecule Deprotonation on an Insulating Surface
2012
Elucidating molecular-scale details of basic reaction steps on surfaces is decisive for a fundamental understanding of molecular reactivity within many fields, including catalysis and on-surface synthesis. Here, the deprotonation of 2,5-dihydroxybenzoic acid (DHBA) deposited onto calcite (101;4) held at room temperature is followed in situ by noncontact atomic force microscopy. After deposition, the molecules form two coexisting phases, a transient striped phase and a stable dense phase. A detailed analysis of high-resolution noncontact atomic force microscopy images indicates the transient striped phase being a bulk-like phase, which requires hydrogen bonds between the carboxylic acid moie…
A stable isotope study of the hydrological and carbon cycle in meromictic lake, Lovojärvi
2012
Lake Lovojärvi, at its deepest point of 17.5 m, is permanently stratified forming two water layers. The mixolimnion (the upper layer, from 0 to 10 m depth) is affected by seasonal changes while the monimolimnion (bottom layer, from 10 to 17.5 m depth) does not mix and is not affected by seasonal changes. As a result, the lake stores large quantities of dissolved inorganic carbon and methane. I used a multiple stable isotope approach to gain insight into the carbon cycle and water balance of Lovojärvi. The δ18O and δ2H profiles reveal that at the 7 m depth in the mixolimnion, there is a sub-surface stream whose isotopic characteristics are similar to surface streams from a nearby mire, sugge…
Aircraft measurements of aerosol particles and trace gases over the Southern Baltic Sea during the BALTIC'15 campaign in 2015
2019
During the BALTIC'15 campaign, conducted in August 2015 over the Southern Baltic Sea, trace gasses (CO2/O3/NOy/SO2) and aerosol particles (number concentration of total/non-volatile/Aitken mode/ Accumulation mode/Coarse mode/refractory black carbon, aerosol extinction coefficient, mass concentration of refractory black carbon were measured). Observations were performed on board of the Alfred Wegener Institute research aircraft Polar 5 during 4 flights: - Scientific flight 1 (SF1) 26 August 2015 - Scientific flight 2 (SF2) 28 August 2015 - Scientific flight 3 (SF3) 28 August 2015 - Scientific flight 4 (SF4) 30 August 2015