scholarly journals Longitudinal remagnetization of uniaxial antiferromagnetic nanoparticles: the role of spontaneous magnetic moment

2022 ◽  
Vol 380 (2217) ◽  
Author(s):  
Igor S. Poperechny
Keyword(s):  
Kinetic Theory ◽  
Magnetic Moment ◽  
Wide Frequency Range ◽  
Magnetic Response ◽  
Anisotropy Axis ◽  
Relaxation Mode ◽  
A Value ◽  
Variation Rate ◽  
Spontaneous Magnetic Moment

A kinetic theory of magnetic response of uniaxial antiferromagnetic nanoparticles is presented. Within the developed framework, a particular case when an external field is applied strictly along the anisotropy axis is considered in detail. Analysis of the relaxation spectrum of an antiferromagnetic particle with a spontaneous magnetic moment is performed. It is shown that in a wide frequency range the magnetic response of such particle is determined entirely by the relaxation mode with the longest time. An analytical expression for this time that explicitly contains a value of the decompensation magnetic moment is derived. Also, simple formulae for both static and dynamic longitudinal magnetic susceptibility of an antiferromagnetic nanoparticle are obtained. According to them, longitudinal susceptibility grows quadratically with the value of the spontaneous magnetic moment. Besides, if the latter is not zero, the change of the static susceptibility with temperature turns out to be non-monotonic. The influence of the spontaneous magnetic moment of the particle on the magnetization curves in strong fields is analysed using both energy approach and kinetic theory. The calculated dependences of the dynamic coercivity on the amplitude and variation rate of the applied field are qualitatively compared with experimental data. This article is part of the theme issue ‘Transport phenomena in complex systems (part 2)’.

Endangered Butterflies and their Non-Native Host Plants: Examining Shifting Values of Belonging in Restoration

2019 ◽  
Vol 3 (1) ◽  
pp. 1-9
Author(s):  
Robert M. Anderson ◽  
Amy M. Lambert
Keyword(s):  
Ecological Restoration ◽  
Native Species ◽  
Puget Sound ◽  
A Value ◽  
The Social ◽  
Remote Island ◽  
Scientific Truth ◽  
Native Host

The island marble butterfly (Euchloe ausonides insulanus), thought to be extinct throughout the 20th century until re-discovered on a single remote island in Puget Sound in 1998, has become the focus of a concerted protection effort to prevent its extinction. However, efforts to “restore” island marble habitat conflict with efforts to “restore” the prairie ecosystem where it lives, because of the butterfly’s use of a non-native “weedy” host plant. Through a case study of the island marble project, we examine the practice of ecological restoration as the enactment of particular norms that define which species are understood to belong in the place being restored. We contextualize this case study within ongoing debates over the value of “native” species, indicative of deep-seated uncertainties and anxieties about the role of human intervention to alter or manage landscapes and ecosystems, in the time commonly described as the “Anthropocene.” We interpret the question of “what plants and animals belong in a particular place?” as not a question of scientific truth, but a value-laden construct of environmental management in practice, and we argue for deeper reflexivity on the part of environmental scientists and managers about the social values that inform ecological restoration.

Perempuan dan Liminalitas dalam Tradisi Perkawinan Adat di Timor Tengah Selatan

2020 ◽  
Vol 6 (1) ◽  
pp. 114
Author(s):  
Marsel Eliaser Liunokas
Keyword(s):  
Qualitative Research ◽  
Research Method ◽  
Literature Study ◽  
Qualitative Research Method ◽  
South Central ◽  
A Value ◽  
Traditional Marriage ◽  
The Village ◽  
As If

Timorese culture is patriarchal in that men are more dominant than women. As if women were not considered in traditional rituals so that an understanding was built that valued women lower than men. However, in contrast to the article to be studied, this would like to see the priority of women’s roles in traditional marriages in Belle village, South Central Timor. The role of women wiil be seen from giving awards to their parents called puah mnasi manu mnasi. This paper aims to look at the meaning of the rituals of puah mnasi maun mnasi and the role and strengths that women have in traditional marriage rituals in the village of Belle, South Central Timor. The method used for this research is a qualitative research method using interview techniques with a number of people in the Belle Villa community and literature study to strengthen this writing. Based on the data obtained this paper shows that the adat rituals of puah mnasi manu mnasi provide a value that can be learned, namely respect for women, togetherness between the two families, and brotherhood that is intertwined due to customary marital affrairs.

Influence of social networks on business processes’ development

2020 ◽  
Vol 19 (12) ◽  
pp. 2225-2252
Author(s):  
E.V. Popov ◽  
V.L. Simonova ◽  
O.V. Komarova ◽  
S.S. Kaigorodova
Keyword(s):  
Social Networks ◽  
Social Media ◽  
Business Models ◽  
Business Processes ◽  
Digital Economy ◽  
Theoretical Understanding ◽  
Sales Channels ◽  
A Value ◽  
The Impact

Subject. The emergence of new ways of interaction between sellers and buyers, the formation of new sales channels and product promotion based on the use of digital economy tools is at the heart of improving the business processes. Social networks became a tool for development; their rapid growth necessitates theoretical understanding and identification of potential application in enterprise's business process digitalization. Objectives. We explore the role of social media in the digitalization of business processes, systematize the impact of social networks on business processes of enterprises in the digital economy. Methods. The theoretical and methodological analysis of social networks as a tool for digitalization of company's business processes rests on the content analysis of domestic and foreign scientific studies, comparison, generalization and systematization. Results. We highlight the key effects of the impact of social networks on the business processes of the company; show that the digitalization of business processes should be considered in the context of a value-based approach, aimed at creating a value through the algorithmization of company operations. We determine that social networks are one of the most important tools for digitalization of company's business processes, as they have a high organizational and management potential. We also systematize the effects of social media on company's business processes. Conclusions. We present theoretical provisions of the impact of social networks on business processes of enterprises, which will enable to model and organize ideas about the development of digital ecosystems and the formation of business models.

scholarly journals Determining the Role of Acidity, Fate and Formation of IEPOX-Derived SOA in CMAQ

Atmosphere ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 707
Author(s):  
Petros Vasilakos ◽  
Yongtao Hu ◽  
Armistead Russell ◽  
Athanasios Nenes
Keyword(s):  
Significant Influence ◽  
Organic Aerosol ◽  
Liquid Water Content ◽  
Anthropogenic Emissions ◽  
So2 Emissions ◽  
Aerosol Acidity ◽  
A Value ◽  
Future Emission ◽  
The Impact

Formation of aerosol from biogenic hydrocarbons relies heavily on anthropogenic emissions since they control the availability of species such as sulfate and nitrate, and through them, aerosol acidity (pH). To elucidate the role that acidity and emissions play in regulating Secondary Organic Aerosol (SOA), we utilize the 2013 Southern Oxidant and Aerosol Study (SOAS) dataset to enhance the extensive mechanism of isoprene epoxydiol (IEPOX)-mediated SOA formation implemented in the Community Multiscale Air Quality (CMAQ) model (Pye et al., 2013), which was then used to investigate the impact of potential future emission controls on IEPOX OA. We found that the Henry’s law coefficient for IEPOX was the most impactful parameter that controls aqueous isoprene OA products, and a value of 1.9 × 107 M atm−1 provides the best agreement with measurements. Non-volatile cations (NVCs) were found in higher-than-expected quantities in CMAQ and exerted a significant influence on IEPOX OA by reducing its production by as much as 30% when present. Consistent with previous literature, a strong correlation of isoprene OA with sulfate, and little correlation with acidity or liquid water content, was found. Future reductions in SO2 emissions are found to not affect this correlation and generally act to increase the sensitivity of IEPOX OA to sulfate, even in extreme cases.

A meta-analysis and review examining a possible role for oxidative stress and singlet oxygen in diverse diseases

2017 ◽  
Vol 474 (16) ◽  
pp. 2713-2731 ◽  
Author(s):  
Athinoula L. Petrou ◽  
Athina Terzidaki
Keyword(s):  
Oxidative Stress ◽  
Excited State ◽  
Singlet Oxygen ◽  
Ground State ◽  
Meta Analysis ◽  
Common Mechanism ◽  
High Electron ◽  
A Value ◽  
First Excited State

From kinetic data (k, T) we calculated the thermodynamic parameters for various processes (nucleation, elongation, fibrillization, etc.) of proteinaceous diseases that are related to the β-amyloid protein (Alzheimer's), to tau protein (Alzheimer's, Pick's), to α-synuclein (Parkinson's), prion, amylin (type II diabetes), and to α-crystallin (cataract). Our calculations led to ΔG≠ values that vary in the range 92.8–127 kJ mol−1 at 310 K. A value of ∼10–30 kJ mol−1 is the activation energy for the diffusion of reactants, depending on the reaction and the medium. The energy needed for the excitation of O2 from the ground to the first excited state (1Δg, singlet oxygen) is equal to 92 kJ mol−1. So, the ΔG≠ is equal to the energy needed for the excitation of ground state oxygen to the singlet oxygen (1Δg first excited) state. The similarity of the ΔG≠ values is an indication that a common mechanism in the above disorders may be taking place. We attribute this common mechanism to the (same) role of the oxidative stress and specifically of singlet oxygen, (1Δg), to the above-mentioned processes: excitation of ground state oxygen to the singlet oxygen, 1Δg, state (92 kJ mol−1), and reaction of the empty π* orbital with high electron density regions of biomolecules (∼10–30 kJ mol−1 for their diffusion). The ΔG≠ for cases of heat-induced cell killing (cancer) lie also in the above range at 310 K. The present paper is a review and meta-analysis of literature data referring to neurodegenerative and other disorders.

scholarly journals Observation of strong excitonic magneto-chiral anisotropy in twisted bilayer van der Waals crystals

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shoufeng Lan ◽  
Xiaoze Liu ◽  
Siqi Wang ◽  
Hanyu Zhu ◽  
Yawen Liu ◽  
...  
Keyword(s):  
Time Reversal ◽  
Room Temperature ◽  
Photochemical Reactions ◽  
Full Width ◽  
Half Maximum ◽  
A Value ◽  
Device Applications ◽  
Spectral Splitting ◽  
Iron Garnet ◽  
Spontaneous Magnetic Moment

AbstractThe interplay between chirality and magnetism generates a distinct physical process, the magneto-chiral effect, which enables one to develop functionalities that cannot be achieved solely by any of the two. Such a process is universal with the breaking of parity-inversion and time-reversal symmetry simultaneously. However, the magneto-chiral effect observed so far is weak when the matter responds to photons, electrons, or phonons. Here we report the first observation of strong magneto-chiral response to excitons in a twisted bilayer tungsten disulfide with the amplitude of excitonic magneto-chiral (ExMCh) anisotropy reaches a value of ~4%. We further found the ExMCh anisotropy features with a spectral splitting of ~7 nm, precisely the full-width at half maximum of the excitonic chirality spectrum. Without an externally applied strong magnetic field, the observed ExMCh effect with a spontaneous magnetic moment from the ferromagnetic substrate of thulium iron garnet at room temperature is favorable for device applications. The unique ExMCh processes provide a new pathway to actively control magneto-chiral applications in photochemical reactions, asymmetric synthesis, and drug delivery.

The role of the media in the formation of shame in the national consciousness

2021 ◽  
Author(s):  
Alaigul Karabaevna Bekboeva
Keyword(s):  
National Identity ◽  
Social Meaning ◽  
National Consciousness ◽  
Social Phenomenon ◽  
Human Relationships ◽  
Social Existence ◽  
A Value ◽  
State And Society ◽  
The Media

This article considers the role of the media as a partner of the state and society, as well as spontaneity. Due to this, media serve as one of the factors in the formation of national self-consciousness and its elements, such as shame. The author analyzes such element of national identity as national shame. It is proved that national shame as a social phenomenon has a social meaning of the regulator of human relationships in social existence. It is noted that national shame is socially determined, has a permanent character, and its socially significant semantic principles are passed from generation to generation as a form of behavior through implantation and interspersing it as a daily norm of people's behavior, giving each act a value-significant meaning.

Renal hemodynamic responses to increased renal venous pressure: role of angiotensin II

1982 ◽  
Vol 243 (3) ◽  
pp. F260-F264 ◽  
Author(s):  
P. R. Kastner ◽  
J. E. Hall ◽  
A. C. Guyton
Keyword(s):  
Angiotensin Ii ◽  
Filtration Rate ◽  
Enzyme Inhibitor ◽  
Venous Pressure ◽  
Renin Secretion ◽  
Ang Ii ◽  
Converting Enzyme ◽  
Filtration Fraction ◽  
A Value

Studies were performed to quantitate the effects of progressive increases in renal venous pressure (RVP) on renin secretion (RS) and renal hemodynamics. RVP was raised in 10 mmHg increments to 50 mmHg. Renin secretion rate increased modestly as RVP was increased to 30 mmHg and then increased sharply after RVP exceeded 30 mmHg. Glomerular filtration rate (GFR), renal blood flow (RBF), and filtration fraction (FF) did not change significantly when RVP was elevated to 50 mmHg. GFR and RBF were also measured after the renin-angiotension system (RAS) was blocked with the angiotensin converting enzyme inhibitor (CEI) SQ 14225. After a 60-min CEI infusion, RBF was elevated (32%), GFR was unchanged, FF was decreased, and total renal resistance (TRR) was decreased. As RVP was increased to 50 mmHg, GFR and FF decreased to 36.3 and 40.0% of control, respectively, RBF returned to a value not significantly different from control, and TRR decreased to 44.8% of control. The data indicate that the RAS plays an important role in preventing reductions in GFR during increased RVP because blockade of angiotensin II (ANG II) formation by the CEI results in marked decreases in GFR at high RVPs. The decreases in GFR after ANG II blockade and RVP elevation were not due to lack of renal vasodilation, since TRR was maintained below while RBF was maintained either above or at the pre-CEI levels.

Microstructure of FCC/BCC Metal Multilayers

1989 ◽  
Vol 160 ◽  
Author(s):  
Nigel M. Jennett ◽  
D.J. Dingley ◽  
Y. Ando
Keyword(s):  
Substrate Temperature ◽  
Magnetic Moment ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Bcc Lattice ◽  
A Value ◽  
Fcc Lattice ◽  
Temperature Window ◽  
Backing Layer

AbstractBilayers of Cu/Fe and Cu/V and multilayers of Ni/Fe have been grown under high vacuum and ultra high vacuum conditions respectively with [111] epitaxy. Multilayer layer thicknesses ranged from 3 monolayers to 15 monolayers per layer. Improved epitaxy of the UHV growth was, we believe, due to the better vacuum although perfect material could only be obtained for growth within a narrow and shifting substrate temperature ‘window’. Possible shortfall in the quality of the Cu backing layer epitaxy was averted by a 2hr anneal at 425°C.In the Fe/Ni multilayers the Fe was observed to adopt the FCC lattice rather than the equilibrium BCC lattice for layer thicknesses less than 10 monolayers. This change of structure coincided with a reduction in sample magnetic moment per volume attributed to a collapse of the Fe moment to a value 7 times less than bulk.

H2/O2 Cycles: Thermodynamic Potentialities and Limits

2003 ◽  
Author(s):  
M. Gambini ◽  
G. L. Guizzi ◽  
M. Vellini
Keyword(s):  
Production Systems ◽  
Renewable Energy Sources ◽  
H2 Production ◽  
Thermodynamic Cycles ◽  
A Value ◽  
Overall Performance ◽  
Definition Of ◽  
Working Parameters ◽  
O2 Production

In this paper, the thermodynamic potentialities and limits of the H2/O2 cycles are investigated. Starting from the conventional gas turbine and steam turbine technology, the paper qualitatively tackles problems related to a change of oxidizer and fuel: from these considerations, an internal combustion steam cycle (ICSC) is analyzed where steam, injected in the combustion chamber together with oxygen and hydrogen, is produced in a regenerative way and plays the important role of inert. A proper parametric analysis is then performed in order to evaluate the influence of the main working parameters on the overall performance of H2/O2 cycles. All the results are carried out neglecting the energy requirements for O2 and H2 production systems, but taking into account their work compression only. This choice permits great freedom in the definition of these thermodynamic cycles and allows general considerations because there is no need of any specification about H2 and/or O2 production systems and their integration with thermodynamic cycles. Therefore this paper can be framed in a context of oxygen and hydrogen centralized production (by nuclear or renewable energy sources for example) and in their distribution as pure gases in the utilization place. Adopting realistic assumptions, TIT of about 1350°C, the potentialities of H2/O2 cycles are very limited: the net efficiency attains a value of about 50%. Instead, adopting futurist assumptions, TIT = I700°C, a different H2/O2 cycle scheme can be proposed and more interesting performance is attained (a net efficiency value over 60%). The thermodynamic and technological aspects are completely addressed in the paper, underlining the great importance of the choice of the main working parameters.

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