Search results for "Coal"
showing 10 items of 354 documents
The dual equivalence of equations and coequations for automata
2015
The transition structure α : X ? X A of a deterministic automaton with state set X and with inputs from an alphabet A can be viewed both as an algebra and as a coalgebra. We use this algebra-coalgebra duality as a common perspective for the study of equations and coequations. For every automaton ( X , α ) , we define two new automata: free ( X , α ) and cofree ( X , α ) representing, respectively, the greatest set of equations and the smallest set of coequations satisfied by ( X , α ) . Both constructions are shown to be functorial. Our main result is that the restrictions of free and cofree to, respectively, preformations of languages and to quotients A * / C of A * with respect to a congr…
Coalition building in the UN Security Council
2014
Political coalitions in the international system are still understudied in International Relations theory. This article claims that the formation of and variations in coalitions in the international system are affected by changes in their bargaining power and bargaining environment related to the global leadership cycle and by long-term organisational changes of the international political system. Identifying the Security Council as the institution in which states are more likely to keep their systemic preferences at the institutional level, the article studies the presence, formation and change of coalitions in the international system by testing variations in the behaviour of the Securit…
Pb(II) adsorption by a novel activated carbon - alginate composite material. A kinetic and equilibrium study.
2016
The adsorption capacity of an activated carbon – calcium alginate composite material (ACAA-Ca) has been tested with the aim of developing a new and more efficient adsorbent material to remove Pb(II) ion from aqueous solution. The study was carried out at pH = 5, in NaCl medium and in the ionic strength range 0.1–0.75 mol L−1. Differential Pulse Anodic Stripping Voltammetry (DP-ASV) technique was used to check the amount of Pb(II) ion removed during kinetic and equilibrium experiments. Different kinetic (pseudo first order, pseudo second order and Vermuelen) and equilibrium (Langmuir and Freundlich) models were used to fit experimental data, and were statistically compared. Calcium alginate …
Protofibril formation of amyloid beta-protein at low pH via a non-cooperative elongation mechanism.
2005
Deposition of the amyloid beta-protein (Abeta) in senile or diffuse plaques is a distinctive feature of Alzheimer's disease. The role of Abeta aggregates in the etiology of the disease is still controversial. The formation of linear aggregates, known as amyloid fibrils, has been proposed as the onset and the cause of pathological deposition. Yet, recent findings suggest that a more crucial role is played by prefibrillar oligomeric assemblies of Abeta that are highly toxic in the extracellular environment. In the present work, the mechanism of protofibril formation is studied at pH 3.1, starting from a solution of oligomeric precursors. By combining static light scattering and photon correla…
Evaluation of the Administrative Phase-Out of Coal Power Plants on the Italian Electricity Market
2020
Although decarbonisation is one of the most important macro-trends of this century, electricity generation from coal power plants is still broadly common. The main goal of this study is to evaluate the impact of a premature coal power plants phase-out on the Italian day-ahead electricity market. For this purpose, two electricity price forecasts, related to different scenarios between 2019 and 2030, and two different hypotheses for the creation of electricity spot price, were compared. The results from the different scenarios show that coal power plants phase-out determines a small variation in electricity price when bid-up is not considered
Further evidence for CCN aerosol concentrations determining the height of warm rain and ice initiation in convective clouds over the Amazon basin
2017
We have investigated how aerosols affect the height above cloud base of rain and ice hydrometeor initiation and the subsequent vertical evolution of cloud droplet size and number concentrations in growing convective cumulus. For this purpose we used in situ data of hydrometeor size distributions measured with instruments mounted on HALO aircraft during the ACRIDICON–CHUVA campaign over the Amazon during September 2014. The results show that the height of rain initiation by collision and coalescence processes (Dr, in units of meters above cloud base) is linearly correlated with the number concentration of droplets (Nd in cm−3) nucleated at cloud base (Dr ≈ 5 ⋅ Nd). Additional cloud processes…
On robustness and dynamics in (un)balanced coalitional games
2012
In this paper we investigate robustness and dynamics for coalitional games with transferable utilities (TU games). In particular we study sequences of TU games. These sequences model dynamic situations in which the values of coalitions of players are not known beforehand, and are subject to changes over time. An allocation rule assigns a payoff to each player in each time period. This payoff is bounded by external restrictions, for example due to contractual agreements. Our main questions are: (i) under which conditions do the allocations converge to a core-element of the game, and (ii) when do the allocations converge to some specific allocation, the so-called nominal allocation? The main …
Birch (Betula spp.) wood biochar is a potential soil amendment to reduce glyphosate leaching in agricultural soils
2015
Glyphosate (N-(phosphonomethyl) glycine), a commonly used herbicide in agriculture can leach to deeper soil layers and settle in surface- and ground waters. To mitigate the leaching of pesticides and nutrients, biochar has been suggested as a potential soil amendment due to its ability to sorb both organic and inorganic substances. However, the efficiency of biochar in retaining agro-chemicals in the soil is likely to vary with feedstock material and pyrolysis conditions. A greenhouse pot experiment, mimicking a crop rotation cycle of three plant genera, was established to study the effects of pyrolysis temperature on the ability of birch (Betula sp.) wood originated biochar to reduce the l…
A Valencian-style Coalition Government: el Botànic
2020
Coalition governments are common in the European political landscape in various tiers ofgovernment. However, such coalitions were an exception in the history of the Valencian Autonomy until 2015, which marked a new stage with the so-called El Botànic governments. Which factors explain this change in the Valencian political system? What are the features of such coalition governments? Can this model be applied to other political systems? This paper addresses these and other issues. First, it looks at what led to coalition governments in both 2015 and 2019. Second, it studies the model of coalition government. The hypothesis tested is this: El Botànic is a coalition government whose success in…
Molecular analysis of the catechol-degrading bacterial community in a coal wasteland heavily contaminated with PAHs
2010
International audience; A PCR-based molecular tool was developed to estimate the diversity of the catechol-degrading bacterial community in a coal wasteland heavily contaminated with PAHS. A degenerate primer pair specific to catA sequences was designed by multiple alignment of known sequences coding a key intermediate of the β-ketoadiapate pathway degrading catechol, namely catechol 1,2-dioxygenase. The specificity of this primer pair was assessed in 21 pure strains by PCR and sequencing. Comparison of the 16S rDNA and catA phylogenies revealed an absence of congruence between these two genes. The primer set was able to amplify catA sequences in DNA extracts from an industrial soil highly …