scholarly journals Applicability of Different Double-Layer Models for the Performance Assessment of the Capacitive Energy Extraction Based on Double Layer Expansion (CDLE) Technique

Energies ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5828
Author(s):  
Zhi Zou ◽  
Longcheng Liu ◽  
Shuo Meng ◽  
Xiaolei Bian ◽  
Yongmei Li

Capacitive energy extraction based on double layer expansion (CDLE) is a renewable method of harvesting energy from the salinity difference between seawater and freshwater. It is based on the change in properties of the electric double layer (EDL) formed at the electrode surface when the concentration of the solution is changed. Many theoretical models have been developed to describe the structural and thermodynamic properties of the EDL at equilibrium, e.g., the Gouy–Chapman–Stern (GCS), Modified Poisson–Boltzmann–Stern (MPBS), modified Donnan (mD) and improved modified Donnan (i-mD) models. To evaluate the applicability of these models, especially the rationality and the physical interpretation of the parameters that were used in these models, a series of single-pass and full-cycle experiments were performed. The experimental results were compared with the numerical simulations of different EDL models. The analysis suggested that, with optimized parameters, all the EDL models we examined can well explain the equilibrium charge–voltage relation of the single-pass experiment. The GCS and MPBS models involve, however, the use of physically unreasonable parameter values. By comparison, the i-mD model is the most recommended one because of its accuracy in the results and the meaning of the parameters. Nonetheless, the i-mD model alone failed to simulate the energy production of the full-cycle CDLE experiments. Future research regarding the i-mD model is required to understand the process of the CDLE technique better.

2018 ◽  
Author(s):  
Jay Joseph Van Bavel

We review literature from several fields to describe common experimental tasks used to measure human cooperation as well as the theoretical models that have been used to characterize cooperative decision-making, as well as brain regions implicated in cooperation. Building on work in neuroeconomics, we suggest a value-based account may provide the most powerful understanding the psychology and neuroscience of group cooperation. We also review the role of individual differences and social context in shaping the mental processes that underlie cooperation and consider gaps in the literature and potential directions for future research on the social neuroscience of cooperation. We suggest that this multi-level approach provides a more comprehensive understanding of the mental and neural processes that underlie the decision to cooperate with others.


Author(s):  
James C.  Root ◽  
Elizabeth Ryan ◽  
Tim A. Ahles

As the population of cancer survivors has grown into the millions, there is increasing emphasis on understanding how late effects of treatment impact survivors’ ability return to work/school, ability to function and live independently, and overall quality of life. Cognitive changes are one of the most feared problems among cancer survivors. This chapter describes the growing literature examining cognitive changes associated with non-central nervous system cancer and cancer treatment. Typical elements of cancer treatment are discussed, followed by a description of clinical presentation, self-reported and objectively assessed cognitive findings, and results of structural and functional neuroimaging research. Genetic and other risk factors for cognitive decline following treatment are identified and discussed, together with biomarkers and animal models of treatment-related effects. This is followed by a discussion of behavioral and pharmacologic treatments. Finally, challenges and recommendations for future research are provided to help guide subsequent research and theoretical models.


Author(s):  
Kelly C. Allison ◽  
Jennifer D. Lundgren

The Diagnostic and Statistical Manual, fifth edition, of the American Psychiatric Association (2013) has designated several disorders under the diagnosis of otherwise specified feeding and eating disorder (OSFED). This chapter evaluates three of these, night eating syndrome (NES), purging disorder (PD), and atypical anorexia nervosa (atypical AN). It also reviews orthorexia nervosa, which has been discussed in the clinical realm as well as the popular press. The history and definition for each is reviewed, relevant theoretical models are presented and compared, and evidence for the usefulness of the models is described. Empirical studies examining the disorders’ independence from other disorders, comorbid psychopathology, and, when available, medical comorbidities, are discussed. Distress and impairment in functioning seem comparable between at least three of these emerging disorders and threshold eating disorders. Finally, remaining questions for future research are summarized.


Membranes ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 129
Author(s):  
Guilherme Volpe Bossa ◽  
Sylvio May

Poisson–Boltzmann theory provides an established framework to calculate properties and free energies of an electric double layer, especially for simple geometries and interfaces that carry continuous charge densities. At sufficiently small length scales, however, the discreteness of the surface charges cannot be neglected. We consider a planar dielectric interface that separates a salt-containing aqueous phase from a medium of low dielectric constant and carries discrete surface charges of fixed density. Within the linear Debye-Hückel limit of Poisson–Boltzmann theory, we calculate the surface potential inside a Wigner–Seitz cell that is produced by all surface charges outside the cell using a Fourier-Bessel series and a Hankel transformation. From the surface potential, we obtain the Debye-Hückel free energy of the electric double layer, which we compare with the corresponding expression in the continuum limit. Differences arise for sufficiently small charge densities, where we show that the dominating interaction is dipolar, arising from the dipoles formed by the surface charges and associated counterions. This interaction propagates through the medium of a low dielectric constant and alters the continuum power of two dependence of the free energy on the surface charge density to a power of 2.5 law.


2007 ◽  
Vol 12 (03) ◽  
pp. 275-293 ◽  
Author(s):  
JENNIFER SEQUEIRA ◽  
STEPHEN L. MUELLER ◽  
JEFFREY E. MCGEE

Theoretical models of entrepreneurship suggest that an individual's intention to start an enterprise is a strong predictor of eventual entrepreneurial action. Less understood are factors that influence the likelihood of entrepreneurial intentions and nascent behavior. In this study, we develop and test several hypotheses about how social network ties and self-efficacy affect entrepreneurial intentions and nascent behavior. We found that a personal network of supportive strong ties coupled with high entrepreneurial self-efficacy increases the likelihood of entrepreneurial intentions and nascent behavior. A personal network of weak ties with practical business knowledge and experience also increases the likelihood of entrepreneurial nascent behavior but not entrepreneurial intentions. In contrast, a personal network of strong ties with practical business knowledge and experience has little effect on either intentions or nascent behavior and may, in fact, suppress both. The contribution of this study to nascent entrepreneurship research and implications for future research are discussed.


1985 ◽  
Vol 7 (4) ◽  
pp. 371-378 ◽  
Author(s):  
W. Jack Rejeski

Subjective estimates of physical work intensity are considered of major importance to those concerned with prescription of exercise. This article reviews major theoretical models which might guide research on the antecedents for ratings of perceived exertion (RPE). It is argued that an active rather than passive view of perception is warranted in future research, and a parallel-processing model is emphasized as providing the needed structure for such reconceptualization. Moreover, existing exercise research is reviewed as support for this latter approach and several suggestions are offered with regard to needed empirical study.


2016 ◽  
Vol 13 (1) ◽  
pp. 76 ◽  
Author(s):  
Herman P. van Leeuwen ◽  
Raewyn M. Town

Environmental context Humic acids are negatively charged soft nanoparticles that play a governing role in the speciation of many ionic and molecular compounds in the environment. The charge density in the humic acid nanoparticle can be very high and the binding of divalent cations such as Ca2+ appears to go far beyond traditional ion pairing or Poisson–Boltzmann electrostatics. A two-state approach, combining counterion condensation in the intraparticulate double layer and classical Donnan partitioning in the bulk of the particle, provides a satisfactory description of the physicochemical speciation. Abstract Experimental data for divalent counterion binding by soil humic acid nanoparticles are set against ion distributions as ensuing from continuous Poisson–Boltzmann electrostatics and a two-state condensation approach. The results demonstrate that Poisson–Boltzmann massively underestimates the extent of binding of Ca2+ by humic acid, and that electric condensation of these counterions within the soft nanoparticulate body must be involved. The measured stability of the Ca2+–humic acid associate is also much greater than that predicted for ion pairing between single Ca2+ ions and monovalent negative humic acid sites, which also points to extensive electrostatic cooperativity within the humic acid particle. At sufficiently high pH, the charge density inside the humic acid entity may indeed become so high that the bulk particle attains a very high and practically flat potential profile throughout. At this limit, all the intraparticulate Ca2+ is at approximately the same electrostatic potential and the status of individual ion pairs has become immaterial. A two-state model, combining counterion condensation in the charged intraparticulate part of the double layer at the particle–medium interface and Donnan partitioning in the uncharged bulk of the humic acid particle, seems to lead the way to adequate modelling of the divalent counterion binding for various particle sizes and different ionic strengths.


Author(s):  
Jason M. Silverman

This essay calls for a thorough reassessment of economics and the Minor Prophets. Since existing economic models based on both Marxism or (Neo-) liberalism are problematic as are many basic economic concepts, new theorizing based on ancient data is necessary. Taking Bourdieu’s “economic field” as a starting frame, this essay considers the material elements of production and consumption in the ancient southern Levant, their patterns and social structures, and some issues in the socioeconomic world of the Minor Prophets. These then raise new questions for sample prophetic passages (Amos, Joel, Haggai, Micah, and Zechariah). The essay points to some issues these considerations raise for analyzing the famous calls for social justice, and it closes by pointing in some potential directions for improved theoretical models in future research.


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