Spontaneous magnetization of the vacuum and the strength of the magnetic field in the hot Universe

The increase of magnetic field of ferromagnetic components under service load and geomagnetic field is induced by the residual magnetic induction and spontaneous magnetization. The stress concentration positions can be found by detecting the magnetic field and the fracture can be avoided. The variation of the residual magnetic intensity of bearing carriers under different damage conditions is studied in this paper; the statistical characteristic of the residual magnetic intensity of the specimens in different residual deformations is got, and a concept of residual magnetic intensity standard deviation is put forward with a lot of experiments and in-depth theoretic analysis. The results indicate that the curves of residual magnetic intensity standard deviation appear obvious turning points when the specimens reach the yield point in different original magnetic field conditions, and that the function between residual magnetic intensities standard deviation, tensile load and strain is established. Therefore, the plastic deformation can be judged by the variation of the magnetic field in their service process, and the damage level can be evaluated consequently, which gives a new reliable method to estimate the deformation of ferromagnetic material.

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The dependence of the spontaneous magnetization on the magnetic field at low temperatures

Czechoslovak Journal of Physics ◽

10.1007/bf01689197 ◽

1955 ◽

Vol 5 (2) ◽

pp. 171-176 ◽

Cited By ~ 2

Author(s):

Luboš Valenta

Keyword(s):

Magnetic Field ◽

Low Temperatures ◽

Spontaneous Magnetization ◽

The Magnetic Field

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Onset Magnetic Field for Rearrangement of Martensite Variants in Ni2MnGa

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.1109 ◽

2007 ◽

Vol 561-565 ◽

pp. 1109-1112

Author(s):

Takashi Fukuda ◽

Nariaki Okamoto ◽

Tomoyuki Kakeshita

Keyword(s):

Magnetic Field ◽

Magnetocrystalline Anisotropy ◽

Spontaneous Magnetization ◽

Parent Phase ◽

Anisotropy Constant ◽

Ferromagnetic Shape Memory Alloy ◽

Twinning Shear ◽

Ferromagnetic Shape Memory ◽

The Magnetic Field ◽

Good Agreement

The magnetic field strength, Hs, at which rearrangement of martensite variants initiates has been investigated in Ni2MnGa ferromagnetic shape memory alloy by magnetization measurements in the [001]P direction ("P" stands for the parent phase). We have also calculated Hs from the magnetocrystalline anisotropy constant Ku, spontaneous magnetization Ms, twinning shear s and twinning stress τreq by considering the condition for the rearrangement of martensite variants reported previously [Int. J. Appl. Electromagnetics and Mechanics, 23 (2006) 45]. The calculated value of Hs is in good agreement with the experimental value for all the examined temperatures. The agreement confirms the applicability of the reported condition.

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Experimental determination of the magnetic-field dependence of the low-temperature spontaneous magnetization of the electron system of hybridized states of cobalt impurities of low concentration (≤0.035 at.%) in a mercury selenide crystal

Low Temperature Physics ◽

10.1063/1.5062165 ◽

2018 ◽

Vol 44 (11) ◽

pp. 1221-1222

Author(s):

T. E. Govorkova ◽

V. I. Okulov

Keyword(s):

Magnetic Field ◽

Low Temperature ◽

Experimental Determination ◽

Field Dependence ◽

Magnetic Field Dependence ◽

Spontaneous Magnetization ◽

Electron System ◽

Mercury Selenide ◽

The Magnetic Field

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Stress Concentration Positions Determination of Ferromagnetic Material Based on Magnetic Test Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.417-418.865 ◽

2009 ◽

Vol 417-418 ◽

pp. 865-868

Author(s):

Feng Yun Yu ◽

Jing Chong Zhang

Keyword(s):

Magnetic Field ◽

Stress Concentration ◽

Spontaneous Magnetization ◽

Tensile Load ◽

Test Point ◽

Test Method ◽

Magnetic Memory ◽

Metal Magnetic Memory ◽

Magnetic Intensity ◽

The Magnetic Field

The magnetic field of ferromagnetic components under service load and geomagnetic field increases is induced by the residual magnetic induction and spontaneous magnetization. The stress concentration positions can be determination by detecting the magnetic field and the fracture can be avoided. The magnetic intensities of the demagnetized samples are tested by metal magnetic memory test method. By tensile test, the relationship between the magnetic memory signals and tensile load is studied, and the metal magnetic memory characteristics of the demagnetized samples under condition that the load keeps a fixed value are obtained. The test result indicates that the magnetic intensities of the samples change greatly after demagnetized; the change of the magnetic intensity of each test point are much different with different tensile displacement; in the later period of hardening phase and necking phase, the magnetic intensity about the side of the stress concentration positions increases along with the increasing of tensile displacement, however that of the other side decreases, that is the gradient of Fracture position increases obviously. Basing on this result by testing the parts of components emphatically where the fatigue failure and breakdown appear easily, the abrupt accident can be avoided.

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Observing the galactic magnetic field

Symposium - International Astronomical Union ◽

10.1017/s0074180900101251 ◽

1967 ◽

Vol 31 ◽

pp. 375-380

Author(s):

H. C. van de Hulst

Keyword(s):

Magnetic Field ◽

Fair Agreement ◽

Solar Neighbourhood ◽

Galactic Magnetic Field ◽

The Magnetic Field

Various methods of observing the galactic magnetic field are reviewed, and their results summarized. There is fair agreement about the direction of the magnetic field in the solar neighbourhood:l= 50° to 80°; the strength of the field in the disk is of the order of 10-5gauss.

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Evolution of Large-Scale Coronal Structures

International Astronomical Union Colloquium ◽

10.1017/s0252921100024945 ◽

1994 ◽

Vol 144 ◽

pp. 29-33

Author(s):

P. Ambrož

Keyword(s):

Magnetic Field ◽

Field Line ◽

Large Scale ◽

Coronal Magnetic Field ◽

Source Surface ◽

Solar Cycles ◽

Characteristic Relationship ◽

The Magnetic Field ◽

Coronal Structures

AbstractThe large-scale coronal structures observed during the sporadically visible solar eclipses were compared with the numerically extrapolated field-line structures of coronal magnetic field. A characteristic relationship between the observed structures of coronal plasma and the magnetic field line configurations was determined. The long-term evolution of large scale coronal structures inferred from photospheric magnetic observations in the course of 11- and 22-year solar cycles is described.Some known parameters, such as the source surface radius, or coronal rotation rate are discussed and actually interpreted. A relation between the large-scale photospheric magnetic field evolution and the coronal structure rearrangement is demonstrated.

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Emergence of Twisted Magnetic Flux Related Sigmoidal Brightening

International Astronomical Union Colloquium ◽

10.1017/s0252921100064630 ◽

2000 ◽

Vol 179 ◽

pp. 263-264

Author(s):

K. Sundara Raman ◽

K. B. Ramesh ◽

R. Selvendran ◽

P. S. M. Aleem ◽

K. M. Hiremath

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Magnetic Flux ◽

Ultra Violet ◽

Active Regions ◽

Morphological Properties ◽

Energy Storage And Conversion ◽

The Sun ◽

X Rays ◽

The Magnetic Field

Extended AbstractWe have examined the morphological properties of a sigmoid associated with an SXR (soft X-ray) flare. The sigmoid is cospatial with the EUV (extreme ultra violet) images and in the optical part lies along an S-shaped Hαfilament. The photoheliogram shows flux emergence within an existingδtype sunspot which has caused the rotation of the umbrae giving rise to the sigmoidal brightening.It is now widely accepted that flares derive their energy from the magnetic fields of the active regions and coronal levels are considered to be the flare sites. But still a satisfactory understanding of the flare processes has not been achieved because of the difficulties encountered to predict and estimate the probability of flare eruptions. The convection flows and vortices below the photosphere transport and concentrate magnetic field, which subsequently appear as active regions in the photosphere (Rust & Kumar 1994 and the references therein). Successive emergence of magnetic flux, twist the field, creating flare productive magnetic shear and has been studied by many authors (Sundara Ramanet al.1998 and the references therein). Hence, it is considered that the flare is powered by the energy stored in the twisted magnetic flux tubes (Kurokawa 1996 and the references therein). Rust & Kumar (1996) named the S-shaped bright coronal loops that appear in soft X-rays as ‘Sigmoids’ and concluded that this S-shaped distortion is due to the twist developed in the magnetic field lines. These transient sigmoidal features tell a great deal about unstable coronal magnetic fields, as these regions are more likely to be eruptive (Canfieldet al.1999). As the magnetic fields of the active regions are deep rooted in the Sun, the twist developed in the subphotospheric flux tube penetrates the photosphere and extends in to the corona. Thus, it is essentially favourable for the subphotospheric twist to unwind the twist and transmit it through the photosphere to the corona. Therefore, it becomes essential to make complete observational descriptions of a flare from the magnetic field changes that are taking place in different atmospheric levels of the Sun, to pin down the energy storage and conversion process that trigger the flare phenomena.

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On the Configuration of the Magnetic Field of β CrB

International Astronomical Union Colloquium ◽

10.1017/s0252921100080933 ◽

1976 ◽

Vol 32 ◽

pp. 613-622

Author(s):

I.A. Aslanov ◽

Yu.S. Rustamov

Keyword(s):

Magnetic Field ◽

Field Strength ◽

Radial Velocity ◽

Magnetic Field Strength ◽

Complex Shape ◽

Rotation Period ◽

Field Variation ◽

Magnetic Field Variation ◽

Secular Variations ◽

The Magnetic Field

SummaryMeasurements of the radial velocities and magnetic field strength of β CrB were carried out. It is shown that there is a variability with the rotation period different for various elements. The curve of the magnetic field variation measured from lines of 5 different elements: FeI, CrI, CrII, TiII, ScII and CaI has a complex shape specific for each element. This may be due to the presence of magnetic spots on the stellar surface. A comparison with the radial velocity curves suggests the presence of a least 4 spots of Ti and Cr coinciding with magnetic spots. A change of the magnetic field with optical depth is shown. The curve of the Heffvariation with the rotation period is given. A possibility of secular variations of the magnetic field is shown.

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Materials for Electron Beam Information Storage

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100062671 ◽

1969 ◽

Vol 27 ◽

pp. 152-153 ◽

Cited By ~ 1

Author(s):

D. E. Speliotis

Keyword(s):

Magnetic Field ◽

Electron Beam ◽

Recent Literature ◽

Electron Beams ◽

Information Storage ◽

The Subject ◽

The Magnetic Field

The interaction of electron beams with a large variety of materials for information storage has been the subject of numerous proposals and studies in the recent literature. The materials range from photographic to thermoplastic and magnetic, and the interactions with the electron beam for writing and reading the information utilize the energy, or the current, or even the magnetic field associated with the electron beam.

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