scholarly journals The measurement of magnetic saturation intensities at different temperatures

1939 ◽  
Vol 170 (943) ◽  
pp. 551-560 ◽  
Keyword(s):  
Magnetic Materials ◽  
Systematic Investigation ◽  
Magnetic Characteristics ◽  
Hard Magnetic Materials ◽  
Fundamental Properties ◽  
Starting Point ◽  
Different Temperatures ◽  
The Moment ◽  
High Degree ◽  
The Magnetic Field

The magnetic properties of alloy systems have assumed increasing importance in recent years. In view of the extreme complexity of the different magnetic characteristics of these alloys, it is evident that a consideration of the more fundamental properties constitute the essential starting point for a systematic investigation. Whilst the behaviour in low magnetic fields may depend largely upon thermal and mechanical treatment, the intensity is known to show less variation, particularly if sufficiently high fields are employed. In the case of many so-called “hard” magnetic materials, however, some thousands of gauss are necessary to produce complete alinement of the elementary domains. If, further, only small quantities are available, the magnetic field required to overcome the shape factor and saturate the material makes the use of an electromagnet essential. The intensity must be measured over a range of temperatures up to the Curie point, so that the variation in the moment of the elementary magnets accompanying a change in structure can be followed. None of the existing methods appears suitable for rapid measurements on a large number of magnetic materials. A new method has been developed capable of measurements on a few cubic millimetres of substance to a high degree of accuracy at any temperature, and it seemed worth while to deal with it in a separate communication.

scholarly journals Developing a reference material set for the magnetic properties of NdFeB alloy-based hard magnetic materials

2019 ◽  
Vol 15 (1) ◽  
pp. 21-27
Author(s):  
E. A. Volegova ◽  
T. I. Maslova ◽  
V. O. Vas’kovskiy ◽  
A. S. Volegov
Keyword(s):  
Magnetic Properties ◽  
Magnetic Materials ◽  
Permanent Magnets ◽  
Magnetic Loss ◽  
Magnetic Hysteresis ◽  
Hysteresis Loops ◽  
Magnetic Hysteresis Loop ◽  
Magnetic Characteristics ◽  
Hard Magnetic Materials ◽  
Certified Values

Introduction The introduction indicates the need for the use of permanent magnets in various technology fields. The necessity of measuring the limit magnetic hysteresis loop for the correct calculation of magnetic system parameters is considered. The main sources of error when measuring boundary hysteresis loops are given. The practical impossibility of verifying blocks of magnetic measuring systems element-by-element is noted. This paper is devoted to the development of reference materials (RMs) for the magnetic properties of hard magnetic materials based on Nd2Fe14B, a highly anisotropic intermetallic compound.Materials and measuring methods Nd-Fe-B permanent magnets were selected as the material for developing the RMs. RM certified values were established using a CYCLE‑3 apparatus included in the GET 198‑2017 State Primary Measurement Standard for units of magnetic loss power, magnetic induction of constant magnetic field in a range from 0.1 to 2.5 T and magnetic flux in a range from 1·10–5 to 3·10–2 Wb.Results and its discussion Based on the experimentally obtained boundary hysteresis loops, the magnetic characteristics were evaluated, the interval of permitted certified values was set, the measurement result uncertainty of certified values was estimated, the RM validity period was established and the first RM batch was released.Conclusion On the basis of conducted studies, the RM type for magnetic properties of NdFeB alloy-based hard magnetic materials was approved (MS NdFeB set). The developed RM set was registered under the numbers GSO 11059–2018 / GSO 11062–2018 in the State RM Register of the Russian Federation.

scholarly journals Authoring Bioconductor workflows with BiocWorkflowTools

F1000Research ◽  
2018 ◽  
Vol 7 ◽  
pp. 431
Author(s):  
Mike L. Smith ◽  
Andrzej K. Oleś ◽  
Wolfgang Huber
Keyword(s):  
Data Analysis ◽  
The Other ◽  
Technical Solution ◽  
Single Source ◽  
Journal Publication ◽  
Source Document ◽  
Manual Intervention ◽  
Starting Point ◽  
The Moment ◽  
High Degree

The Bioconductor Gateway on the F1000Research platform is a channel for peer-reviewed and citable publication of end-to-end data analysis workflows rooted in the Bioconductor ecosystem. In addition to the largely static journal publication, it is hoped that authors will also deposit their workflows as executable documents on Bioconductor, where the benefits of regular code testing and easy updating can be realized. Ideally these two endpoints would be met from a single source document. However, so far this has not been easy, due to lack of a technical solution that meets both the requirements of the F1000Research article submission format and the executable documents on Bioconductor. Submission to the platform requires a LaTeX file, which many authors traditionally have produced by writing an Rnw document for Sweave or knitr. On the other hand, to produce the HTML rendering of the document hosted by Bioconductor, the most straightforward starting point is the R Markdown format. Tools such as pandoc enable conversion between many formats, but typically a high degree of manual intervention used to be required to satisfactorily handle aspects such as floating figures, cross-references, literature references, and author affiliations. The BiocWorkflowTools package aims to solve this problem by enabling authors to work with R Markdown right up until the moment they wish to submit to the platform.

Device for determining static magnetic characteristics of specimens of hard-magnetic materials

1971 ◽  
Vol 14 (11) ◽  
pp. 1726-1728 ◽  
Author(s):  
M. A. Artemova ◽  
O. Yu. Bagalei ◽  
M. I. Grobovitskii ◽  
V. I. Zingerman
Keyword(s):  
Magnetic Materials ◽  
Magnetic Characteristics ◽  
Hard Magnetic Materials

Microwires coated by glass: A new family of soft and hard magnetic materials

2000 ◽  
Vol 15 (10) ◽  
pp. 2107-2113 ◽  
Author(s):  
A. Zhukov ◽  
J. González ◽  
J. M. Blanco ◽  
M. Vázquez ◽  
V. Larin
Keyword(s):  
Heat Treatment ◽  
Magnetic Materials ◽  
Nanocrystalline Structure ◽  
Initial Permeability ◽  
Magnetic Characteristics ◽  
Hard Magnetic Materials ◽  
New Family ◽  
Magnetic Softness ◽  
Metallic Wires ◽  
Amorphous Microwires

The Taylor–Ulitovski technique was employed for fabrication of tiny ferromagnetic amorphous and nanocrystalline metallic wires covered by an insulating glass coating with magnetic properties of great technological interest. A single and large Barkhausen jump was observed for microwires with positive magnetostriction. Negative magnetostriction microwires exhibited almost unhysteretic behavior with an easy axis transverse to the wire axis. Enhanced magnetic softness (initial permeability, μι, up to 14000) and giant magneto impedance (GMI) effect (up to 140% at 10 MHz) was observed in amorphous CoMnSiB microwires with nearly zero magnetostriction after adequate heat treatment. Large sensitivity of GMI and magnetic characteristics on external tensile stresses was observed. Upon heat treatment, FeSiBCuNb amorphous microwires devitrificated into a nanocrystalline structure with enhanced magnetic softness. The magnetic bistability was observed even after the second crystallization process (increase of switching field by more than 2 orders of magnitude up to 5.5 kA/m). Hard magnetic materials were obtained as a result of decomposition of metastable phases in Co–Ni–Cu and Fe–Ni–Cu microwires fabricated by Taylor–Ulitovski technique when the coercivity increased up to 60 kA/m. A magnetic sensor based on the magnetic bistability was designed.

scholarly journals Magnetic Properties of Fe, Co and Ni Based Nanopowders Produced by Chemical-Metallurgy Method

2021 ◽  
Vol 23 (1) ◽  
pp. 3
Author(s):  
Tien Hiep Nguyen ◽  
Y. Konyukhov ◽  
Nguyen Van Minh ◽  
D. Y. Karpenkov ◽  
V. V. Levina ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Materials ◽  
Magnetic Measurements ◽  
Chemical Reduction ◽  
Pure Metal ◽  
Fine Tuning ◽  
Magnetic Characteristics ◽  
Hard Magnetic Materials ◽  
Time Parameters ◽  
Co Precipitation

This research study describes the magnetic properties of Fe, Co and Ni metallic nanopowders (NPs) and their ternary nanocomposites (NCs), which can be used as fillers in radio-wave absorbing composite materials and coatings, as well as for magnetic protection of banknotes and security paper. The nanopowders were prepared by the chemical metallurgy method. The desired properties of Fe, Co and Ni NPs and NCs were achieved by co-precipitation, the addition of surfactants and changes in reduction temperature and time parameters. Magnetic measurements showed that all samples of pure metal NPs are semi-hard magnetic materials. The added surfactants have distinct effects on the dimensional and magnetic characteristics of Fe, Co and Ni NPs. Ni–Co–Fe NCs are also mainly semi-hard magnetic materials. Fine-tuning of their composition and chemical reduction temperatures allows controlling the values of Ms and Hc in large ranges from 49 to 197 A·m2/kg and from 4.7 to 60.6 kA/m, respectively.

L’absence chez Michel Butor. L’Emploi du temps et Degrés

2012 ◽  
pp. 66-80
Author(s):  
Michał Mrozowicki
Keyword(s):  
Human Memory ◽  
Point Of View ◽  
Narrative Discourse ◽  
The Novel ◽  
Michel Butor ◽  
Starting Point ◽  
One Year ◽  
The Moment ◽  
Narrative Mode ◽  
The City

Michel Butor, born in 1926, one of the leaders of the French New Novel movement, has written only four novels between 1954 and 1960. The most famous of them is La Modification (Second thoughts), published in 1957. The author of the paper analyzes two other Butor’s novels: L’Emploi du temps (Passing time) – 1956, and Degrés (Degrees) – 1960. The theme of absence is crucial in both of them. In the former, the novel, presented as the diary of Jacques Revel, a young Frenchman spending a year in Bleston (a fictitious English city vaguely similar to Manchester), describes the narrator’s struggle to survive in a double – spatial and temporal – labyrinth. The first of them, formed by Bleston’s streets, squares and parks, is symbolized by the City plan. During his one year sojourn in the city, using its plan, Revel learns patiently how to move in its different districts, and in its strange labyrinth – strange because devoid any centre – that at the end stops annoying him. The other, the temporal one, symbolized by the diary itself, the labyrinth of the human memory, discovered by the narrator rather lately, somewhere in the middle of the year passed in Bleston, becomes, by contrast, more and more dense and complex, which is reflected by an increasinly complex narration used to describe the past. However, at the moment Revel is leaving the city, he is still unable to recall and to describe the events of the 29th of February 1952. This gap, this absence, symbolizes his defeat as the narrator, and, in the same time, the human memory’s limits. In Degrees temporal and spatial structures are also very important. This time round, however, the problems of the narration itself, become predominant. Considered from this point of view, the novel announces Gerard Genette’s work Narrative Discourse and his theoretical discussion of two narratological categories: narrative voice and narrative mode. Having transgressed his narrative competences, Pierre Vernier, the narrator of the first and the second parts of the novel, who, taking as a starting point, a complete account of one hour at school, tries to describe the whole world and various aspects of the human civilization for the benefit of his nephew, Pierre Eller, must fail and disappear, as the narrator, from the third part, which is narrated by another narrator, less audacious and more credible.

Nucleation fields and grain boundaries in hard magnetic materials

1993 ◽  
Vol 29 (6) ◽  
pp. 2878-2880 ◽  
Author(s):  
T. Schrefl ◽  
H.F. Schmidts ◽  
J. Fidler ◽  
H. Kronmuller
Keyword(s):  
Grain Boundaries ◽  
Magnetic Materials ◽  
Hard Magnetic Materials

scholarly journals The estimation of electric moment in solution by the temperature coefficient method. Part I.—Experimental method and the electric moments of some benzyl compounds

1933 ◽  
Vol 142 (846) ◽  
pp. 173-197 ◽  
Keyword(s):  
Single Molecule ◽  
Polar Solvent ◽  
Fundamental Equation ◽  
Absolute Temperature ◽  
Electric Moment ◽  
Avogadro’S Number ◽  
Boltzmann Gas ◽  
Different Temperatures ◽  
The Moment ◽  
Coefficient Method

The theory of the estimation of the electric moment of molecules dissolved in a non-polar solvent is now well known. The fundamental equation is P 2∞ = 4 π /3 N (α 0 + μ 2 /3 k T) (1) in which the symbols have the following significance: P 2∞ the total polarizability of the solute per grain molecule at infinite dilution, N Avogadro’s number, α 0 the moment induced in a single molecule by unit electric field, k the Boltzmann gas constant, T the absolute temperature, and μ the permanent electric moment of the molecule. This equation is of the form P 2∞ = A + B/T, (2) where A = 4 π /3 Nα 0 and B = 4 π /9 . N μ 2 / k , from which it follows that if A and B are constant, i. e ., independent of temperature, then each may be evaluated from a series of measurements of P 2∞ at different temperatures or alternatively B (and hence μ ) may be obtained from one value of P 2∞ at one temperature, provided that A can be obtained by some independent method.

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