scholarly journals Performance of Microporous Carbon Electrodes for Supercapacitors: Comparing Graphene with Disordered Materials

2018 ◽  
Author(s):  
Trinidad Mendez-Morales ◽  
Nidhal Ganfoud ◽  
Zhujie Li ◽  
Matthieu Haefele ◽  
Benjamin Rotenberg ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Carbon Materials ◽  
Structural Features ◽  
Carbon Electrodes ◽  
Disordered Materials ◽  
Surface Charges ◽  
The Past ◽  
Counter Ions ◽  
The One ◽  
Electrodes For Supercapacitors

Over the past decades, the specific surface area and the pore size distribution have been identified as the main structural features that govern the performance of carbon-based supercapacitors. As a consequence, graphene nanostructures have been identified as strong candidates for maximizing their capacitance. However, this hypothesis could not be thoroughly tested so far due to the difficulty of synthesizing perfect materials with high pore accesibility and a sufficiently large density. Here we perform molecular simulations of a series of perforated graphene electrodes with single pore sizes ranging from 7 to 10 Angstroms in contact with an adsorbed ionic liquid, and compare the capacitances (using various metrics) to the one obtained with a typical disordered nanoporous carbon. The latter displays better performances, an observation that we explain by analyzing the structure of the liquid inside the pores. It appears that although the smaller pores are responsible for the largest surface charges, larger ones are also necessary to store the counter-ions and avoid the formation of detrimental opposite charges on the carbon. These results rationalize the need for disordered or activated carbon materials to design efficient supercapacitors.

scholarly journals Performance of Microporous Carbon Electrodes for Supercapacitors: Comparing Graphene with Disordered Materials

2018 ◽  
Author(s):  
Trinidad Mendez-Morales ◽  
Nidhal Ganfoud ◽  
Zhujie Li ◽  
Matthieu Haefele ◽  
Benjamin Rotenberg ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Carbon Materials ◽  
Structural Features ◽  
Carbon Electrodes ◽  
Disordered Materials ◽  
Surface Charges ◽  
The Past ◽  
Counter Ions ◽  
The One ◽  
Electrodes For Supercapacitors

Over the past decades, the specific surface area and the pore size distribution have been identified as the main structural features that govern the performance of carbon-based supercapacitors. As a consequence, graphene nanostructures have been identified as strong candidates for maximizing their capacitance. However, this hypothesis could not be thoroughly tested so far due to the difficulty of synthesizing perfect materials with high pore accesibility and a sufficiently large density. Here we perform molecular simulations of a series of perforated graphene electrodes with single pore sizes ranging from 7 to 10 Angstroms in contact with an adsorbed ionic liquid, and compare the capacitances (using various metrics) to the one obtained with a typical disordered nanoporous carbon. The latter displays better performances, an observation that we explain by analyzing the structure of the liquid inside the pores. It appears that although the smaller pores are responsible for the largest surface charges, larger ones are also necessary to store the counter-ions and avoid the formation of detrimental opposite charges on the carbon. These results rationalize the need for disordered or activated carbon materials to design efficient supercapacitors.

scholarly journals Biomass-derived carbon electrodes for supercapacitors and hybrid solar cells: towards sustainable photo-supercapacitors

2021 ◽  
Author(s):  
Nilanka M. Keppetipola ◽  
Céline Olivier ◽  
Thierry Toupance ◽  
Ludmila Cojocaru
Keyword(s):  
Electrical Conductivity ◽  
Solar Cells ◽  
Electrochemical Properties ◽  
Carbon Materials ◽  
Low Cost ◽  
Carbon Electrodes ◽  
Hybrid Solar Cells ◽  
Potential Applications ◽  
Electrodes For Supercapacitors

Due to their outstanding electrochemical properties, electrical conductivity, flexibility, and low-cost, carbon materials open up new opportunities for the design of compact devices with a wide variety of potential applications....

scholarly journals Performance of microporous carbon electrodes for supercapacitors: Comparing graphene with disordered materials

2019 ◽  
Vol 17 ◽  
pp. 88-92 ◽  
Author(s):  
Trinidad Méndez-Morales ◽  
Nidhal Ganfoud ◽  
Zhujie Li ◽  
Matthieu Haefele ◽  
Benjamin Rotenberg ◽  
...  
Keyword(s):  
Microporous Carbon ◽  
Carbon Electrodes ◽  
Disordered Materials ◽  
Electrodes For Supercapacitors

Study of the Molecular Architecture of Keratin Filaments by Electron Microscopy

1982 ◽  
Vol 40 ◽  
pp. 118-119
Author(s):  
U. Aebi ◽  
P. Rew ◽  
T.-T. Sun
Keyword(s):  
Electron Microscopy ◽  
Structural Organization ◽  
Cell Types ◽  
Structural Features ◽  
Molecular Architecture ◽  
The Past ◽  
Keratin Filaments ◽  
Different Types ◽  
10 Nm Filaments ◽  
Different Cell Types

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.

Al-Rasm al-ʿUthmānī: Towards Correct Pronunciation and the Preclusion of Ambiguity

2011 ◽  
Vol 13 (2) ◽  
pp. 201-171
Author(s):  
Nāṣir Al-Dīn Abū Khaḍīr
Keyword(s):  
Specific Pattern ◽  
Writing Style ◽  
The Third ◽  
The Past ◽  
Different Ages ◽  
Correct Pronunciation ◽  
The One ◽  
The Mind

The ʿUthmānic way of writing (al-rasm al-ʿUthmānī) is a science that specialises in the writing of Qur'anic words in accordance with a specific ‘pattern’. It follows the writing style of the Companions at the time of the third caliph, ʿUthmān b. ʿAffān, and was attributed to ʿUthmān on the basis that he was the one who ordered the collection and copying of the Qur'an into the actual muṣḥaf. This article aims to expound on the two fundamental functions of al-rasm al-ʿUthmānī: that of paying regard to the ‘correct’ pronunciation of the words in the muṣḥaf, and the pursuit of the preclusion of ambiguity which may arise in the mind of the reader and his auditor. There is a further practical aim for this study: to show the connection between modern orthography and the ʿUthmānic rasm in order that we, nowadays, are thereby able to overcome the problems faced by calligraphers and writers of the past in their different ages and cultures.

General Trend of Negative Transference Number in Li Salt/Ionic Liquid Mixtures

2019 ◽  
Author(s):  
Nicola Molinari ◽  
Jonathan P. Mailoa ◽  
Boris Kozinsky
Keyword(s):  
Ionic Liquid ◽  
Transference Number ◽  
Liquid Mixtures ◽  
Single Linkage ◽  
Self Diffusion ◽  
Wide Range ◽  
Single Linkage Cluster ◽  
Concentrated Solution ◽  
The One ◽  
Dynamics Simulations

We show that strong cation-anion interactions in a wide range of lithium-salt/ionic liquid mixtures result in a negative lithium transference number, using molecular dynamics simulations and rigorous concentrated solution theory. This behavior fundamentally deviates from the one obtained using self-diffusion coefficient analysis and agrees well with experimental electrophoretic NMR measurements, which accounts for ion correlations. We extend these findings to several ionic liquid compositions. We investigate the degree of spatial ionic coordination employing single-linkage cluster analysis, unveiling asymmetrical anion-cation clusters. Additionally, we formulate a way to compute the effective lithium charge that corresponds to and agrees well with electrophoretic measurements and show that lithium effectively carries a negative charge in a remarkably wide range of chemistries and concentrations. The generality of our observation has significant implications for the energy storage community, emphasizing the need to reconsider the potential of these systems as next generation battery electrolytes.<br>

TARP DVIEJŲ KOLONŲ: XVIII A. PABAIGOS – XIX A. PRADŽIOS VILNIAUS MASONŲ KASDIENYBĖ SIMBOLIKOJE

2018 ◽  
pp. 144-163
Author(s):  
Daiva Milinkevičiūtė
Keyword(s):  
Daily Life ◽  
The Other ◽  
Daily Routine ◽  
The Past ◽  
Secular World ◽  
National Characteristics ◽  
Conservative Christian ◽  
The Subject ◽  
The One ◽  
Craft Guilds

The Age of Enlightenment is defined as the period when the universal ideas of progress, deism, humanism, naturalism and others were materialized and became a golden age for freemasons. It is wrong to assume that old and conservative Christian ideas were rejected. Conversely, freemasons put them into new general shapes and expressed them with the help of symbols in their daily routine. Symbols of freemasons had close ties with the past and gave them, on the one hand, a visible instrument, such as rituals and ideas to sense the transcendental, and on the other, intense gnostic aspirations. Freemasons put in a great amount of effort to improve themselves and to create their identity with the help of myths and symbols. It traces its origins to the biblical builders of King Solomon’s Temple, the posterity of the Templar Knights, and associations of the medieval craft guilds, which were also symbolical and became their link not only to each other but also to the secular world. In this work we analysed codified masonic symbols used in their rituals. The subject of our research is the universal Masonic idea and its aspects through the symbols in the daily life of the freemasons in Vilnius. Thanks to freemasons’ signets, we could find continuity, reception, and transformation of universal masonic ideas in the Lithuanian freemasonry and national characteristics of lodges. Taking everything into account, our article shows how the universal idea of freemasonry spread among Lithuanian freemasonry, and which forms and meanings it incorporated in its symbols. The objective of this research is to find a universal Masonic idea throughout their visual and oral symbols and see its impact on the daily life of the masons in Vilnius. Keywords: Freemasonry, Bible, lodge, symbols, rituals, freemasons’ signets.

The Invention of Papal History

2019 ◽  
Author(s):  
Stefan Bauer
Keyword(s):  
Catholic Reformation ◽  
History Writing ◽  
Historical Texts ◽  
The Past ◽  
History Of ◽  
Cultural Standards ◽  
Commissioned Works ◽  
The One ◽  
Late Renaissance ◽  
The Church

How was the history of post-classical Rome and of the Church written in the Catholic Reformation? Historical texts composed in Rome at this time have been considered secondary to the city’s significance for the history of art. The Invention of Papal History corrects this distorting emphasis and shows how history-writing became part of a comprehensive formation of the image and self-perception of the papacy. By presenting and fully contextualizing the path-breaking works of the Augustinian historian Onofrio Panvinio (1530–68), this book shows what type of historical research was possible in the late Renaissance and the Catholic Reformation. Historiography in this period by no means consisted entirely of commissioned works written for patrons; rather, a creative interplay existed between, on the one hand, the endeavours of authors to explore the past and, on the other hand, the constraints of patronage and ideology placed on them. This book sheds new light on the changing priorities, mentalities, and cultural standards that flourished in the transition from the Renaissance to the Catholic Reformation.

“Ambiguist” Statesmanship

Worldview ◽  
1960 ◽  
Vol 3 (9) ◽  
pp. 7-8
Author(s):  
Will Herberg
Keyword(s):  
Foreign Policy ◽  
Fixed Points ◽  
Natural Law ◽  
The Other ◽  
Moral Decision ◽  
Actual Situation ◽  
The Past ◽  
Mixed Feelings ◽  
Rational Mind ◽  
The One

John Courtney Murray's writing cannot fail to be profound and instructive, and I have profited greatly from it in the course of the past decade. But I must confess that his article, "Morality and Foreign Policy" (Worldview, May), leaves me in a strange confusion of mixed feelings. On the one hand, I can sympathize with what I might call the historical intention of the natural law philosophy he espouses, which I take to be the effort to establish enduring structures of meaning and value to serve as fixed points of moral decision in the complexities of the actual situation. On the other hand, I am rather put off by the calm assurance he exhibits when he deals with these matters, as though everything were at bottom unequivocally rational and unequivocally accessible to the rational mind. And I am really distressed at what seems to 3ie to be his woefully inadequate appreciation of the position of the "ambiguists," among whom I cannot deny I count myself.

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