Angular Dispersion and its Relationship with Other Magnetic Parameters in Permalloy Films

1962 ◽  
pp. 1107-1109
Author(s):  
Robert W. Olmen ◽  
Sidney M. Rubens
Keyword(s):  
Angular Dispersion ◽  
Magnetic Parameters

Physical methods of research and monitoring

2019 ◽  
Vol 85 (1(I)) ◽  
pp. 35-44
Author(s):  
S. G. Sandomirski
Keyword(s):  
Heat Treatment ◽  
Coercive Force ◽  
Remanent Magnetization ◽  
Structural Changes ◽  
Mechanical Load ◽  
Magnetic Hysteresis ◽  
Steel Structures ◽  
Magnetic Characteristics ◽  
Magnetic Parameters ◽  
Saturation Intensity

The main magnetic parameters sensitive to the structure of steels are the parameters of their saturation loop of magnetic hysteresis: the coercive force Hcs and remanent magnetization Mrs. The saturation magnetization or saturation intensity Mr is most sensitive to the phase composition of steels. The variety of steel grades and modes of technological treatment (e.g., heat treatment, mechanical load) determined the use of magnetic structurescopy and magnetic characteristics — the coercive force Hc, remanent magnetization Mr , and specific hysteresis losses Wh on the subloops of the magnetic hysteresis of steels — as control parameters in diagnostics of the stressed and structural states of steel structures and pipelines. It has been shown that changes in Hc, Mr , and Wh are more sensitive to structural stresses and structures of steels than the parameters of the saturation hysteresis loop of magnetic hysteresis (Hcs, Mrs, and Mrs). The formulas for calculating Hc, Mr and Wh are presented to be used for estimation of changes in the parameters upon heat treatment of steels. Features of the structural sensitivity of the subloop characteristics and expediency of their use for magnetic structural and phase analyzes are determined. Thus, the range of changes in Ìr attributed to the structural changes in steels upon gradual Hm decrease is many times wider compared to the range of possible changes in Mrs under the same conditions. Conditions (relations between the magnetic parameters) and recommendations regarding the choice of the field strength Hm are given which provide the justified use of Hc, Mr and Wh parameters in magnetic structurescopy

Synthesis of nickel selenites, their solubility and bonding in them

1982 ◽  
Vol 47 (8) ◽  
pp. 2069-2076 ◽  
Author(s):  
Miroslav Ebert ◽  
Zdeněk Mička ◽  
Ilona Peková
Keyword(s):  
Magnetic Properties ◽  
Hydrogen Bonding ◽  
Solubility Diagram ◽  
Reflectance Spectroscopy ◽  
Chloride Anion ◽  
Fluoride Anion ◽  
Infrared Absorption Spectroscopy ◽  
Magnetic Parameters ◽  
Nickel Cation ◽  
Spectrochemical Series

The solubility diagram of the NiSeO3-SeO2-H2O system at 25 °C was studied, and on its basis, Ni(HSeO3)2.2 H2O was prepared. This selenite and NiSeO3.2 H2O were investigated by infrared absorption spectroscopy and by electronic reflectance spectroscopy and their magnetic properties were determined. Based on the infrared spectra, the force constants of the selenium-oxygen bonds were determined and the hydrogen bonding was characterized. The electronic reflectance spectra and the magnetic parameters indicate an octahedral arrangement of the coordination sphere of the nickel cation and characterize the selenite anion as a ligand that in the spectrochemical series assumes a position between the fluoride anion and water and in the nephelauxetic series, between ethylenediamine and the chloride anion.

scholarly journals Quantitative estimates of average geomagnetic axial dipole dominance in deep geological time

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Andrew J. Biggin ◽  
Richard K. Bono ◽  
Domenico G. Meduri ◽  
Courtney J. Sprain ◽  
Christopher J. Davies ◽  
...  
Keyword(s):  
Power Law ◽  
Geomagnetic Field ◽  
Recent Observation ◽  
Observational Constraint ◽  
Angular Dispersion ◽  
Geological Time ◽  
Future Studies ◽  
Axial Dipole ◽  
Quantitative Estimates

AbstractA defining characteristic of the recent geomagnetic field is its dominant axial dipole which provides its navigational utility and dictates the shape of the magnetosphere. Going back through time, much less is known about the degree of axial dipole dominance. Here we use a substantial and diverse set of 3D numerical dynamo simulations and recent observation-based field models to derive a power law relationship between the angular dispersion of virtual geomagnetic poles at the equator and the median axial dipole dominance measured at Earth’s surface. Applying this relation to published estimates of equatorial angular dispersion implies that geomagnetic axial dipole dominance averaged over 107–109 years has remained moderately high and stable through large parts of geological time. This provides an observational constraint to future studies of the geodynamo and palaeomagnetosphere. It also provides some reassurance as to the reliability of palaeogeographical reconstructions provided by palaeomagnetism.

scholarly journals PM2.5 Magnetic Properties in Relation to Urban Combustion Sources in Southern West Africa

Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 496
Author(s):  
Aruã da Silva Leite ◽  
Jean-François Léon ◽  
Melina Macouin ◽  
Sonia Rousse ◽  
Ricardo Ivan Ferreira da Trindade ◽  
...  
Keyword(s):  
Narrow Range ◽  
Excellent Correlation ◽  
Magnetic Mineralogy ◽  
Particulate Emission ◽  
Magnetic Parameters ◽  
Element Carbon ◽  
Physico Chemical ◽  
Magnetic Investigation ◽  
Combustion Sources ◽  
Carbon Concentrations

The physico-chemical characteristics of particulate matter (PM) in African cities remain poorly known due to scarcity of observation networks. Magnetic parameters of PM are robust proxies for the emissions of Fe-bearing particles. This study reports the first magnetic investigation of PM2.5 (PM with aerodynamic size below 2.5 μm) in Africa performed on weekly PM2.5 filters collected in Abidjan (Ivory Coast) and Cotonou (Benin) between 2015 and 2017. The magnetic mineralogy is dominated by magnetite-like low coercivity minerals. Mass normalized SIRM are 1.65 × 10−2 A m2 kg−1 and 2.28 × 10−2 A m2 kg−1 for Abidjan and Cotonou respectively. Hard coercivity material (S-ratio = 0.96 and MDF = 33 mT) is observed during the dry dusty season. Wood burning emits less iron oxides by PM2.5 mass when compared to traffic sources. PM2.5 magnetic granulometry has a narrow range regardless of the site or season. The excellent correlation between the site-averaged element carbon concentrations and SIRM suggests that PM2.5 magnetic parameters are linked to primary particulate emission from combustion sources.

Structural, spectral, electrical and magnetic parameters evaluation of Er3+-substituted Ni0·8Zn0·2Fe2O4 nanoparticles synthesized by wet chemical route

2021 ◽  
Vol 602 ◽  
pp. 412574
Author(s):  
Tahira Akhter ◽  
Muhammad Asif Yousuf ◽  
Muhammad Asghar ◽  
Ibrahim A. Alsafari ◽  
Akmal Jamil ◽  
...  
Keyword(s):  
Chemical Route ◽  
Magnetic Parameters ◽  
Wet Chemical ◽  
Wet Chemical Route

Determination of Intrinsic Magnetic Parameters of SmCo5 Phase in Sintered Samples

2005 ◽  
Vol 498-499 ◽  
pp. 129-133 ◽  
Author(s):  
Marcos Flavio de Campos ◽  
Fernando José Gomes Landgraf
Keyword(s):  
Powder Metallurgy ◽  
Domain Wall ◽  
Kerr Effect ◽  
Critical Diameter ◽  
Optical Microscope ◽  
Domain Theory ◽  
Magnetic Domains ◽  
Magnetic Parameters ◽  
Intrinsic Parameters

SmCo5 magnets are usually produced by powder metallurgy route, including milling, compaction and orientation under magnetic field, sintering and heat treatment. The samples produced by powder metallurgy, with grain size around 10 μm, are ideal for determination of intrinsic parameters. The first step for determination of intrinsic magnetic parameters is obtaining images of domain structure in demagnetized samples. In the present study, the domain images were produced by means of Kerr effect, in a optical microscope. After the test of several etchings, Nital appears as the most appropriate for observation of magnetic domains by Kerr effect. Applying Stereology and Domain Theory, several intrinsic parameters of SmCo5 phase were determined: domain wall energy 120 erg/cm2, critical diameter for single domain particle size 2 μm and domain wall thickness 60 Å. In the case of SmCo5, and also other phases with high magnetocrystalline anisotropy, Domain Theory presents several advantages when compared with Micromagnetics.

scholarly journals Angular dispersion compensation for acousto-optic devices used for ultrashort-pulsed laser micromachining

2001 ◽  
Vol 9 (4) ◽  
pp. 200 ◽  
Author(s):  
B.K. Ann Ngoi ◽  
Krishnan Venkatakrishnan ◽  
L.E.N. Lim ◽  
B. Tan
Keyword(s):  
Dispersion Compensation ◽  
Pulsed Laser ◽  
Laser Micromachining ◽  
Angular Dispersion ◽  
Ultrashort Pulsed Laser
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