59 resultados para Nash equilibrium
Resumo:
This paper reviews Alfred Marshall's attempts to reconcile increasing returns and competition from the early economic writings to the later editions of his Principles. It is shown that while Marshall's final solution to the problem involved naming external economies the cause of increasing returns in a regime of competition , both the life cycle of the firm and internal economies remained necessary to his argument. Their function was to give some operation al content to the elusive concept of external economies.
Resumo:
In this paper we examine the properties of stable coalitions under sequential and simultaneous bargaining by competing labor unions. We do this using the Nash bargaining solution and various notions of stability, namely, Nash, coalitional, contractual and core stability. (C) 2011 Elsevier B.V. All rights reserved,
Resumo:
Variable-temperature magnetic susceptibility measurements in the solid state of the bis complex of tris(1-pyrazolyl)-methane with Fe(II), [Fe(tpm)2](ClO4)2, suggest the existence of singlet-quintet spin crossover with the singlet isomer largely favored at room temperature. In acetonitrile solution, measurement of the absorption spectrum as a function of temperature reveals a spin equilibrium with the quintet population varying from ca. 6% at 233 K to ca. 30% at 295 K. When the complex in solution is irradiated with a laser pulse at wavelengths within the ligand field absorption band of the singlet isomer, ground-state depletion occurs within the pulse duration followed by fast recovery to the original absorbance level with a time constant of 25 +/- 5ns. The recovery time is virtually independent of temperature over the range +23 to -43-degrees-C, but the signal:noise ratio of the transient signals increases with decreasing temperature. The effect was observable at several monitoring wavelengths spanning the LF and MLCT absorption regions of the complex but only when the irradiation wavelength fell within the LF absorption region. Irradiation within the MLCT band produced no effect other than that of laser pulse scatter. The observations are interpreted in terms of photoperturbation of the singlet-quintet spin state equilibrium, which in this case occurs solely through excitation in the ligand field absorption region of the complex and is the first reported instance of this type for a spin-crossover complex in solution.
Resumo:
The equilibrium responses of three new colorimetric plastic film sensors for CO2 as a function of % CO2 and temperature are described. The results fit a model in which there is a 1:1 equilibrium reaction between the deprotonated form of the dye (present in the film as an ion pair) and CO2. The 0-50% and 0-90% response and recovery times of each of these films when exposed to an alternating atmosphere of air and 5% CO2 are determined and in two cases are typically less than 3 s. The shelf life of the films is long (many months); however, prolonged use of the films leads to the permanent generation of the protonated form of the dye over a period of 20-100 h. A possible cause of this latter effect is discussed.
Resumo:
We report herein the screening, optimisation and scale up to 100 g of a bioreduction process that employs an in situ product removal (ISPR) technique to overcome the inherent equilibrium problem associated with the coupled-substrate approach to biocatalytic carbonyl reduction. This technique allowed the valuable chiral alcohol, (S)-2-bromo-2-cyclohexen-1-ol, to be isolated in 88% yield and 99.8% ee without the need for further purification, validating the general applicability of this experimental setup.
Resumo:
This paper examines simple parimutuel betting games under asymmetric information, with particular attention to differences between markets in which bets are submitted simultaneously versus sequentially. In the simultaneous parimutuel betting market, all (symmetric and asymmetric) Bayesian-Nash equilibria are generically characterized as a function of the number of bettors and the quality of their private information. There always exists a separating equilibrium, in which all bettors follow their private signals. This equilibrium is unique if the number of bettors is sufficiently large. In the sequential framework, earlier bets have information externalities, because they may reveal private information of bettors. They also have payoff externalities, because they affect the betting odds. One effect of these externalities is that the separating equilibrium disappears if the number of betting periods is sufficiently large. (C) 2006 Elsevier B.V. All rights reserved.
Resumo:
Using ion carbon beams generated by high intensity short pulse lasers we perform measurements of single shot mean charge equilibration in cold or isochorically heated solid density aluminum matter. We demonstrate that plasma effects in such matter heated up to 1 eV do not significantly impact the equilibration of carbon ions with energies 0.045-0.5 MeV/nucleon. Furthermore, these measurements allow for a first evaluation of semiempirical formulas or ab initio models that are being used to predict the mean of the equilibrium charge state distribution for light ions passing through warm dense matter.
Resumo:
The present research investigates the uptake of phosphate ions from aqueous solutions using acidified laterite (ALS), a by-product from the production of ferric aluminium sulfate using laterite. Phosphate adsorption experiments were performed in batch systems to determine the amount of phosphate adsorbed as a function of solution pH, adsorbent dosage and thermodynamic parameters per fixed P concentration. Kinetic studies were also carried out to study the effect of adsorbent particle sizes. The maximum removal capacity of ALS observed at pH 5 was 3.68 mg P g-1. It was found that as the adsorbent dosage increases, the equilibrium pH decreases, so an adsorbent dosage of 1.0 g L-1 of ALS was selected. Adsorption capacity (qm) calculated from the Langmuir isotherm was found to be 2.73 mg g-1. Kinetic experimental data were mathematically well described using the pseudo first-order model over the full range of the adsorbent particle size. The adsorption reactions were endothermic, and the process of adsorption was favoured at high temperature; the ΔG and ΔH values implied that the main adsorption mechanism of P onto ALS is physisorption. The desorption studies indicated the need to consider a NaOH 0.1M solution as an optimal solution for practical regeneration applications.
Resumo:
Mesoporous materials were used as adsorbents for dye removal in different media: non-ionic, buffered and saline. The mesoporous materials used were commercial (silica gel) as well as as-synthesised materials (SBA-15 and a novel mesoporous carbon). Dye adsorption onto all the materials was very fast and the equilibrium was reached before 1h. The pH has a significant influence on the adsorption capacity for the siliceous materials since the electrostatic interactions are the driving forces. However, the influence of the pH on the adsorption capacity of the carbonaceous material was lower, since the van der Waals interactions are the driving forces. The ionic strength has a great impact on the siliceous materials adsorption capacity, being their adsorption capacity in a buffered medium six times higher than the corresponding to a non-ionic medium. Nevertheless, ionic strength does not influence on the dye adsorption on the mesoporous carbon. Overall, the as-synthesised carbon material presents a clear potential to treat dye effluents, showing high adsorption capacity (qe≈200mg/g) in all the pH range studied (from 3 to 11); even at low concentrations (Ce≈10mg/L) and at short contact times (te<30min).
Resumo:
Polybrominated diphenyl ethers (PBDEs) are a group of flame retardants that have been in use since the 1970s. They are included in the list of hazardous substances known as persistent organic pollutants (POPs) because they are extremely hazardous to the environment and human health. PBDEs have been extensively used in industry and manufacturing in Taiwan, thus its citizens are at high risk of exposure to these chemicals.
An assessment of the environmental fate of these compounds in the Zhuoshui river and Changhua County regions of western Taiwan, and also including the adjacent area of the Taiwan Strait, was conducted for three high risk congeners, BDE-47, -99 and -209, to obtain information regarding the partitioning, advection, transfer and long range transport potential of the PBDEs in order to identify the level of risk posed by the pollutants in this region.
The results indicate that large amounts of PBDEs presently reside in all model compartments – air, soil, water, and sediment – with particularly high levels found in air and especially in sediment. The high levels found in sediment, particularly for BDE-209, are significant, since there is the threat of these pollutants entering the food chain, either directly through benthic feeding, or through resuspension and subsequent feeding in the pelagic region of the water column which is a distinct possibility in the strong currents found within the Taiwan Strait. Another important result is that a substantial portion of emissions leave the model domain directly through advection, particularly for BDE-47 (58%) and BDE-209 (75%), thus posing a risk to adjacent communities.
Model results were generally in reasonable agreement with available measured concentrations. In air, model concentrations are in reasonably good agreement with available measured values. For both BDE-47 and -99, model concentrations are a factor of 2-3 higher and BDE-209 within the range of measured values. In soil, model results are somewhat less than measured values. In sediment, model results are at the high end of measured values.