The role of BEG 1,2-butanediol as a reducing agent in Co-based nanoparticle synthesis in the polyol process has not been well-detailed yet. So, we focused on the determination of the main active ...species derived from 1,2-butanediol (BEG) in Co-based nanoparticle synthesis and their reducing abilities through density functional theory (DFT) calculations. In the reaction medium, BEG is deprotonated by the hydroxyl ions introduced in the solution then oxidized by the metal ions. The progression of reduction and dissociation reactions of metal ions is relatively related to the reducing ability of polyols. Three species which are: dianion, monoanion and neutral molecule of BEG were considered in our investigation. The highest occupied orbital energy was estimated for the different configurations. Considering the experimental and theoretical studies, the monoanion state was suggested as the most active form. A comparative study was carried out between three polyols: BEG, PEG (1, 2-propanediol) and EG (Ethylen glycol), which are the most used solvents in Co-based nanoparticle synthesis. We showed that the highest occupied orbital energy of BEG monoanion state is relatively high compared to PEG and EG ones. Thus, BEG could reduce metal ions more easily by giving its electrons and its use can make the reaction kinetics faster.
Graphical Abstract
SYNOPSIS
The role of BEG 1,2-butanediol as a reducing agent in Co-based nanoparticle synthesis in polyol process has not been well-detailed yet. Our theoretical calculations show that the highest occupied orbital energy of BEG monoanion state is relatively high compared to most used solvents in Co-based nanoparticle synthesis. Thus, BEG could reduce metal ions more easily by giving its electrons and its use make the reaction kinetics faster.
We derive the exact Helmholtz free energy (HFE) of the standard and staggered one-dimensional Blume–Emery–Griffiths (BEG) model in the presence of an external longitudinal magnetic field. We discuss ...in detail the thermodynamic behavior of the ferromagnetic version of the model, which exhibits magnetic field-dependent plateaux in the z-component of its magnetization at low temperatures. We also study the behavior of its specific heat and entropy, both per site, at finite temperature. The degeneracy of the ground state, at T=0, along the lines that separate distinct phases in the phase diagram of the ferromagnetic BEG model is calculated, extending the study of the phase diagram of the spin-1 antiferromagnetic (AF) Ising model in S.M. de Souza and M.T. Thomaz, J. Magn. and Magn. Mater. 354 (2014) 205 5. We explore the implications of the equality of phase diagrams, at T=0, of the ferromagnetic BEG model with K|J|=−2 and of the spin-1 AF Ising model for D|J|>12.
•The exact thermodynamics of the D=1 standard and staggered Blume-Emery-Griffiths model.•The one-dimensional BEG model in the presence of a longitudinal magnetic field.•The degeneracy of the ground state, at T=0, of the ferromagnetic BEG model.•The degeneracy of the ground state, at T=0, of the ferromagnetic BEG model.•The degeneracy of the ground state, at T=0, of the anti-ferromagnetic spin-1 Ising model.•The ferromagnetic BEG model versus the AF spin-1 longitudinal Ising model at low temperature.
Four new genera and six new species of fossil seed (Buarcospermum tetragonium, Lignierispermum maroneae, Lobospermum glabrum, L. rugosum, L. stampanonii, Rugonella trigonospermum) are described from ...five Early Cretaceous mesofossil floras from Portugal and eastern North America. The four genera are distinguished by differences in size, shape, and details of seed anatomy, but all are unusual in having an outer seed envelope with a distinctive anatomical structure that surrounds the nucellus and the integument. The integument is extended apically into a long, narrow micropylar tube. The four new genera are part of a diverse, but previously unrecognized, complex of extinct plants that was widespread in Early Cretaceous vegetation and that coexisted in similar habitats with early angiosperms. The distinctive structure of these seeds, and the strong similarities to other fossil seeds (Ephedra, Ephedripites, Erdtmanispermum, Raunsgaardispermum, and some Bennettitales) already known from the Early Cretaceous, suggests that this newly recognized complex of extinct plants, together with Bennettitales, Erdtmanithecales, and Gnetales (the BEG group), is phylogenetically closely related.
Chronicling a Dynasty on the Make Ghereghlou, Kioumars
Journal of the American Oriental Society,
10/2017, Letnik:
137, Številka:
4
Journal Article
Recenzirano
This article studies Qāsim Beg Ḥayātī Tabrīzī’s unpublished account of Ṣafavid history, which has long been considered lost. Ḥayātī’s account—dedicated, in 961/1554, to Shah Ṭahmāsp’s ...sister, Princess Mihīn Begum (d. 969/1562)—spans the period between the formative years of the Ṣafaviyya Sufi order under Ṣafī al-Dīn Isḥāq Ardabīlī (d. 735/1334) and the early years of the reign of Shah Ismāʿīl (907–30/1501–24). Emphasis is given to the way in which it fills in the gaps of our knowledge insofar as the pre-dynastic and early dynastic phases of Ṣafavid history as well as the administrative history of the Ṣafavid shrine in Ardabīl are concerned.
“History begins with writing,” because writing is the most important and reliable tool for transmitting knowledge to future generations. It has made use of various materials for this very purpose for ...centuries and one of these materials is paper. The transmission of paper to the Islamic world and its subsequent vast production allowed books to become widespread and made paper the most important medium for written transmissions. We do not have a great deal of first-hand information on how books were prepared other than the compilation process which we know due to the presence of some compilers’ anecdotes regarding the characteristics of the compilation which is an aspect of its meaning. However, producing a book as a commodity is just as important as compilation in the sense of reproduction and circulation of knowledge. This article introduces the accounts of ʿAbd al-Razzāq al-Tirmidhī, a copyist who was fully engaged in the copying stage of book production. The intellectual and scientific life of the period will be discussed based on his list, which was recorded on the last page of a copy of the Mathnawī written in Samarqand in 1417. Several questions will also be raised for future studies.
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