The objective of this study was a theoretical explanation of the reason causing a new phenomenon in NDT. When some drill stems for oil and gas field operated through a long period of time were maintained, NDT personnel discovered that the magnetic particle inspection could be carried out on them without magnetization, and only had to apply suspension upon them. An item analysis was conducted on...

The demagnetization of a hard ferromagnetic layer via the fringing fields of domain walls created by reversing the moment of a neighboring soft ferromagnetic layer is explored experimentally. An unusual oscillatory decay of the magnetic moment of the hard layer is observed using structures in which the demagnetization occurs after a few hundred cycles. This surprising observation is confirmed o...

We introduce a method and software to process demagnetization data for a rapid and integrative estimation of characteristic remanentmagnetization (ChRM) components. The virtual directions (VIDI) of a paleomagnetic site are “all” possible directions that can be calculated from a given demagnetization routine of “n” steps (being m the number of specimens in the site). If the ChRM can be defined f...

INTRODUCTION: Most of the previous functional studies focus on the magnitude change of the MR signal. However, as well as the magnitude change, the phase change of the BOLD fMRI signal [1-3] and the frequency shift of the functional MR signal [4] have also been detected in human. Since no fMRI signal phase change should be detected if the fMRI signal is only consisted of extravascular signal an...

Adiabatic demagnetization is currently gaining strong interest in searching for alternatives to (3)He-based refrigeration techniques for achieving temperatures below 2 K. The main reasons for that are the recent shortage and high price of the rare helium isotope (3)He. Here we report the discovery of a large magnetocaloric effect in the intermetallic compound YbPt2Sn, which allows adiabatic dem...

The La0.67Sr0.33MnO3 /BaFe11.3~ZnSn!0.7O19 ~LSMO/BaM! composites have been prepared by cosintering the LSMO and the BaM powders. The microstructural, magnetic, and magnetoresistive ~MR! properties of those systems were systematically studied. Due to the magnetic coupling between the LSMO ~a soft magnet metal! and BaM ~a hard magnet insulator! grains, the low-field MR sensitivity was reduced and...

The thermal demagnetization of pseudo-single-domain (PSD) magnetite (Fe3O4) particles, which govern the magnetic signal in many igneous rocks, is examined using off-axis electron holography. Visualization of a vortex structure held by an individual Fe3O4 particle (~250 nm in diameter) during in situ heating is achieved through the construction and examination of magnetic-induction maps. Stepwis...

It is widely believed that electron dynamics in the shock front is essentially collisionless and determined by the quasistationary magnetic and electric ®elds in the shock. In thick shocks the electron motion is adiabatic: the magnetic moment is conserved throughout the shock and v? / B. In very thin shocks with large cross-shock potential (the last feature is typical for shocks with strong ele...