Surface magnetic field

Table 1. Surface magnetic field and the radius of stars by the conservation of the magnetic flux.

Figure 6.8 Schematic view of solar surface. Magnetic field lines rise from one sunspot into the corona and plunge back down into the other. At the top of the loop, the filed lines can become twisted to produce a solar flare that lights up the chromosphere below.

In principle, the relativistic winds of newly born magnetars (neutron stars with surface magnetic fields about 1015 G) can directly accelerate particles up to 1021 eV [48], [49] but they are very rare events in the Galaxy. 

Fig. 46. Schematic order parameter (magnetization) profiles m(z) near a free surface, according to mean field theory. Various cases arc shown (a) Extrapolation length X positive. The transition of the surface from the disordered state to the ordered state is driven by the transition in the bulk ( ordinary transition ). The shaded area indicates the definition of the surface magnetization ms. (b) Extrapolation length X = oo. The transition of the surface is called "special transition ( surfacc-bulk-multicritical point ), (c), (d) Extrapolation length X < 0, temperature above the bulk critical temperature (c) or below it (d). The transition between states (c) and (d) is called the extraordinary transition , (c) Surface magnetic field Hi competes with bulk order (mi, > 0, 0 < H such that mi < -mb). In this case a domain of oppositely oriented magnetization with macroscopic thickness ( welting layer ) separated by an interface from the bulk would form at the surface, ir the system is at the coexistence curve (T < Tv, H = 0). From Binder (1983).

Pig. 57. (a) Location of first-order, second-order and tricritical wetting transitions in she Ising model via Monte Carlo studies of a 50 x 50 x 40 system (with two free 50 x 50 surfaces which have exchange, /s between nearest neighbors, while all other exchange constants are equal to J, and where a negative surface magnetic field H acts) by a study of the surface layer... 

Earth s magnetic fielcJ is 5 x lO T, measured at the equator, its maximum surface magnetic field is 7 x 10 T, measured at the south magnetic pole. 

Laser-induced predissociation in the presence of a surface magnetic field, and dissociation dynamics in the presence of an intense laser field have been treated... 

H - surface magnetic field strength He - azimuthal magnetic field strength Jc = critical current density Pn = loss per unit volume of normal substrate Psc = loss per unit volume of superconducting substrate Tsc = critical temperature of substrate = temperature of maximum loss... 

The basic idea in surface magnetic field (surmac) devices is to create a magnetic fence surrounding a large volume of reacting plasma (Fig. 1). The field is created by an inner set... 

The selectivity of the particle-appended BODIPY host for Pb " " detection is approximately 12-fold higher compared to the free host. To evaluate the selectivity of the sensing material, various metal ions such as Li+, Na+, Mg +, K+, Ca " ", Cu " ", Zn " ", Ag" ", Cd ", and Hg + were investigated in aqueous solution, but only Pb + induced a large CHEF effect. The authors assumed that the chemical detection of Pb2+ is facilitated by the cooperative effect of multiple noncovalent interactions as a result of the preorganization of the hosts on the solid surface. Magnetic field-assisted removal of Pb + from water and blood with the hybrid material rendered remediation yields of up to 97%. 

Remark In the field of structural investigations one must mention the work of Kuzmenko et al. (1972, 1976, 1980, 1984a,b, 1986a,b) and Kuzmenko and Melnikov (1982, 1988) who have studied the amorphous crystalline transition in Yb films. It is observed to occur under particular experimental conditions application of a perpendicular magnetic field, a flow of helium gas, an oblique deposition and a short current pulse. The most important parameter is the thickness of the sample. The transition is explained in terms of avalanche (shock) crystallization. However no XRD or EDP data are exhibited and the crystalline phases of the metal (fee or hep) are not defined. One must notice that Haussler and Bauman (1980) using a parallel (to the surface) magnetic field do not observe this transition at 4,2 K. 

Its maximum surface magnetic field is 7 X KT T, measured at the south magnetic pole. 

SPM Scanned Probe Microscopy Very flat surface Any field e.g. mechan. vibration recorded with laser probe same with magnetic, electric or thermal field 1-100nm 1-100 nm Surface-magnetic field, surface-thermal conductivity, etc. 39a... 

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