3,249 research outputs found
The Alexander legend
No full text: Članek predstavi spis Legenda o Aleksandru, ki je nastal kmalu po letu 628 v kontekstu bizantinske imperialne propagande, ki si je prizadevala bizantinski imperij predstaviti kot četrto kraljestvo iz Danielove prerokbe o nasledstvu štirih kraljestev. Avtor najprej
obravnava prerokbi o nasledstvu štirih kraljestev iz Danielove knjige. Drugo poglavje članka
je namenjeno analizi Afrahatovega Pokaza o vojnah kot primera sirske politične teologije.
V tretjem poglavju članka avtor oriše osnovne teze Legende o Aleksandru, čemur doda tudi
prevode najpomembnejših odlomkov tega spisa. V zadnjem, četrtem poglavju avtor poda
komentar k Legendi o Aleksandru in obravnava vprašanje datacije, temeljnih tez ter avtorstva
Legende o Aleksandru. V zaključku je izpostavljena pomembnost spisa za apokaliptično
literaturo tako v krščanskem kot v islamskem svetu.The article introduces the Syriac Alexander Legend, a text that was written in the
context of the Byzantine imperial propaganda and aimed to present the Byzantine Empire
as the fourth empire from Daniel’s prophecy on the four kingdoms. In the first chapter, the
author analyzes the prophecy on the succession of the four kingdoms contained in the Book
of Daniel. The second chapter is dedicated to the analysis of Aphrahat’s Demonstration
on Wars, which is presented as an example of Syriac political theology. In the third chapter,
the author sketches the story line of the Alexander legend and offers a Slovenian translation
of the selected passages of the Alexander Legend. In the fourth chapter, a short commentary
on the Alexander legend is provided. The commentary addresses the origins, basic theological
concepts, and authorship of the Alexander legend. In the conclusion of the paper, the author
highlights the importance of the Alexander Legend for the subsequent apocalyptic literature
in the Christian as well as in the Islamic world
Adsorption-driven translocation of polymer chain into nanopores
No full textThe polymer translocation into nanopores is generally facilitated by external driving forces, such as electric or hydrodynamic fields, to compensate for entropic restrictions imposed by the confinement. We investigate the dynamics of translocation driven by polymer adsorption to the confining walls that is relevant to chromatographic separation of macromolecules. By using the self-consistent field theory, we study the passage of a chain trough a small opening from cis to trans compartments of spherical shape with adsorption potential applied in the trans compartment. The chain transfer is modeled as the Fokker-Plank diffusion along the free energy landscape of the translocation pass represented as a sum of the free energies of cis and trans parts of the chain tethered to the pore opening. We investigate how the chain length, the size of trans compartment, the magnitude of adsorption potential, and the extent of excluded volume interactions affect the translocation time and its distribution. Interplay of these factors brings about a variety of different translocation regimes. We show that excluded volume interactions within a certain range of adsorption potentials can cause a local minimum on the free energy landscape, which is absent for ideal chains. The adsorption potential always leads to the decrease of the free energy barrier, increasing the probability of successful translocation. However, the translocation time depends non-monotonically of the magnitude of adsorption potential. Our calculations predict the existence of the critical magnitude of adsorption potential, which separates favorable and unfavorable regimes of translocation. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4720505]http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000305090900048&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Physics, Atomic, Molecular & ChemicalSCI(E)EI11ARTICLE21null13
Critical conditions of polymer chromatography: An insight from SCFT modeling
No full textIn polymer chromatography, chain molecules are separated by molecular weight, size, and chemical composition due to adsorption and exclusion in nanoporous substrates. Three regimes of separation are distinguished depending on the adsorption strength and the pore size. In the regime of size exclusion chromatography, the adsorption energy is weak and the separation is entropy-driven with larger molecules having shorter retention times. On the opposite, in the regime of adsorption chromatography, enthalpy gain due to strong adsorption energy prevails over entropy loss, and the retention time of smaller molecules is shorter. We study the intermediate regime of so-called critical conditions, at which the entropic and enthalpic effects are mutually compensated, and the partition coefficient does not depend on the polymer molecular weight. Using the self-consistent field theory of tethered polymer chains, we confirm that for ideal chains the critical conditions are justified, albeit they depend on the pore size. However, for real chains with the excluded volume effect, the critical conditions hold only approximately, and the discrepancy increases as the pore size decreases. We show that it is important to consider three characteristic adsorption states: chains adsorbed at the external surface, chains adsorbed completely inside the pores, and partially translocated chains or "flowers" with a "root" adsorbed inside the pore and a "stem" hanging outside. The interplay of different adsorption mechanisms and the pore size distribution inherent to real substrates may lead to the manifestation of apparent critical adsorption conditions within the inherent deviation of experimental data. (C) 2013 AIP Publishing LLC.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000321148200051&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Physics, Atomic, Molecular & ChemicalSCI(E)EI2ARTICLE24null13
Pore Structure Compartmentalization for Advanced Characterization of Metal–Organic Framework Materials
No full textMetal–organic frameworks (MOFs)
are nanoporous crystals
which are widely used as selective adsorbents, separation membranes,
catalysts, gas and energy storage media, and drug delivery vehicles.
The unique adsorption and transport properties of MOFs are determined
by their complex three-dimensional (3D) networks of pores, cages,
and channels that differ in size, shape, and chemical composition.
While the morphological structure of MOF crystals is known, practical
MOF materials are rarely ideal crystals. They contain secondary phases,
binders, residual chemicals, and various types of defects. It is of
paramount importance to evaluate the degree of crystallinity and accessibility
of different pore compartments to adsorb guest molecules. To this
end, we recently suggested the method of fingerprint isotherms based
on the comparison of the experimentally measured adsorption isotherms
and theoretical isotherms on ideal MOF crystals produced by Monte
Carlo (MC) simulations and decomposed with respect to different pore
compartments [Parashar, S.ACS Appl. Nano Mater. 2021, 4, 5531–5540 and Dantas, S.; Neimark, A. V. ACS Appl. Mater. Interfaces 2020, 12, 15595–15605]. In this work, we develop an automated algorithm for pore network
compartmentalization that is a prerequisite for calculations of the
fingerprint isotherms. The proposed algorithm partitions the unit
cell into realistically shaped compartments based on the geometric
pore size distribution. The proposed method is demonstrated on several
characteristic systems, including Cu-BTC, IRMOF-1, UiO-66, PCN-224,
ZIF-412, and 56 structures from the CoRE MOF database
Vapor-to-Droplet Transition in a Lennard-Jones Fluid: Simulation Study of Nucleation Barriers Using the Ghost Field Method
No full textWe report a comprehensive Monte Carlo (MC) simulation study of the vapor-to-droplet transition in Lennard-Jones fluid confined to a spherical container with repulsive walls, which is a case study system to investigate
homogeneous nucleation. The focus is made on the application of a modified version of the ghost field method
(Vishnyakov, A.; Neimark, A. V. J. Chem. Phys. 2003, 119, 9755) to calculate the nucleation barrier. This
method allows one to build up a continuous trajectory of equilibrium states stabilized by the ghost field
potential, which connects a reference droplet with a reference vapor state. Two computation schemes are
employed for free energy calculations, direct thermodynamic integration along the constructed trajectory and
umbrella sampling. The nucleation barriers and the size dependence of the surface tension are reported for
droplets containing from 260 to 2000 molecules. The MC simulation study is complemented by a review of
the simulation methods applied to computing the nucleation barriers and a detailed analysis of the vapor-to-droplet transition by means of the classical nucleation theory
Pore Structure Compartmentalization for Advanced Characterization of Metal–Organic Framework Materials
No full textMetal–organic frameworks (MOFs)
are nanoporous crystals
which are widely used as selective adsorbents, separation membranes,
catalysts, gas and energy storage media, and drug delivery vehicles.
The unique adsorption and transport properties of MOFs are determined
by their complex three-dimensional (3D) networks of pores, cages,
and channels that differ in size, shape, and chemical composition.
While the morphological structure of MOF crystals is known, practical
MOF materials are rarely ideal crystals. They contain secondary phases,
binders, residual chemicals, and various types of defects. It is of
paramount importance to evaluate the degree of crystallinity and accessibility
of different pore compartments to adsorb guest molecules. To this
end, we recently suggested the method of fingerprint isotherms based
on the comparison of the experimentally measured adsorption isotherms
and theoretical isotherms on ideal MOF crystals produced by Monte
Carlo (MC) simulations and decomposed with respect to different pore
compartments [Parashar, S.ACS Appl. Nano Mater. 2021, 4, 5531–5540 and Dantas, S.; Neimark, A. V. ACS Appl. Mater. Interfaces 2020, 12, 15595–15605]. In this work, we develop an automated algorithm for pore network
compartmentalization that is a prerequisite for calculations of the
fingerprint isotherms. The proposed algorithm partitions the unit
cell into realistically shaped compartments based on the geometric
pore size distribution. The proposed method is demonstrated on several
characteristic systems, including Cu-BTC, IRMOF-1, UiO-66, PCN-224,
ZIF-412, and 56 structures from the CoRE MOF database
„Natur muss gefühlt werden“ – Alexander von Humboldt, Vordenker einer ökologischen Weltsicht und Protagonist „transversaler Vernunft“
No full textDer Text erinnert zum 250sten Geburtsjahr an Alexander von Humboldt, ein Vordenker für eine ökologische Sicht der Welt und ein früher Protagonist „transversaler Vernunft“. Er ist als Ideengeber für die „neuen Naturtherapien“, für die Integrative Therapie und für eine ökologische Sicht in der Psychotherapie eine unverzichtbare Quelle. Einige aus dieser Perspektive wichtige Aspekte seines Denkens und Werkes werden aufgezeigt. Er ist ein Referenzautor für transversales und integratives Konzeptualisieren in unserer Zeit.The text commemorates the 250th year of birth of Alexander von Humboldt, a thought leader for an ecological view of the world and an early protagonist of „transversal reason“. He is an indispensable source of ideas for the „new nature therapies“, for integrative therapy and for an ecological viewpoint in psychotherapy. Some important aspects of his thinking and work are shown from this perspective. He is a reference author for transversal and integrative conceptualization in our time.https://www.fpi-publikation.de/polyloge/25-2019-petzold-h-g-mathias-wiedemann-u-natur-muss-gefuehlt-werden-alexander-v-humboldt/peerReviewedpublishedVersio
„Nature must be felt“ – Alexander von Humboldt, pioneer of an ecological worldview and protagonist of „transversal reason“
No full textDer Text erinnert zum 250sten Geburtsjahr an Alexander von Humboldt, ein Vordenker für eine ökologische Sicht der Welt und ein früher Protagonist „transversaler Vernunft“. Er ist als Ideengeber für die „neuen Naturtherapien“, für die Integrative Therapie und für eine ökologische Sicht in der Psychotherapie eine unverzichtbare Quelle. Einige aus dieser Perspektive wichtige Aspekte seines Denkens und Werkes werden aufgezeigt. Er ist ein Referenzautor für transversales und integratives Konzeptualisieren in unserer Zeit.The text commemorates the 250th year of birth of Alexander von Humboldt, a thought leader for an ecological view of the world and an early protagonist of „transversal reason“. He is an indispensable source of ideas for the „new nature therapies“, for integrative therapy and for an ecological viewpoint in psychotherapy. Some important aspects of his thinking and work are shown from this perspective. He is a reference author for transversal and integrative conceptualization in our time.https://www.fpi-publikation.de/gruene-texte/17-2019-petzold-h-g-mathias-wiedemann-u-natur-muss-gefuehlt-werden-alexander-v-humboldt/peerReviewedpublishedVersio
Alexander v. Sandoval:A Setback for Civil Rights
No full textThis article confronts the serious implications of a recent U.S. Supreme Court decision, Alexander v. Sandoval, which eliminated an important legal avenue for civil rights plaintiffs. For over 35 years, individuals have been allowed to bring lawsuits directly challenging violations of rights set forth in the federal regulations implementing Title VI of the 1964 Civil Rights Act. Because these actions could be grounded in proof of disparate impact, rather than discriminatory intent, they allowed for some claims that could not go forward under other legal authorities, such as the Fourteenth Amendment. While the author concludes by identifying key remaining options, he highlights the real damage done by this decision
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