Curie surface

The electrochemical quartz crystal microbalance (EQCM) is a very useful technique for detecting small mass changes at the electrode surface that accompany electrochemical processes. In 1880, Jacques and Pierre Curie discovered that when stress was applied to some crystals, such as quartz, it resulted in an electrical potential across the... 

The rate of the active transport of sodium ion across frog skin depends both on the electrochemical potential difference between the two sides of this complex membrane (or, more exactly, membrane system) and also on the affinity of the chemical reaction occurring in the membrane. This combination of material flux, a vector, and chemical flux (see Eq. 2.3.26), which is scalar in nature, is possible according to the Curie principle only when the medium in which the chemical reaction occurs is not homogeneous but anisotropic (i.e. has an oriented structure in the direction perpendicular to the surface of the membrane or, as is sometimes stated, has a vectorial character). 

Laboratoire de Reactivite de Surface, University Pierre and Marie Curie (UPMC), UMR-7609 CNRS, 4place Jussieu, cosier 178, 75252 Paris Cedex 05, France... 

Universite Pierre et Marie Curie, Laboratoire de Reactivite de Surface, CNRS UMR 7609, 4, Place Jussieu, 75252 Paris, France ... 

Cobalt s Curie point is 1,121°C, and its melting point is 1,495°C. About 25% of all cobalt mined in the world is used as an alloy with other metals. The most important is the alloy alnico, which consists of nickel, aluminum, and cobalt. Alnico is used to make powerful permanent magnets with many uses, such as CT, PET, and MRl medical instruments. It is also used for electroplating metals to give a fine surface that resists oxidation. 

Molten iron Density 7.00 g/cm at 1,564°C vapor pressure 0.06 torr at 1,600° C, and 1 torr at 1,850°C, respectively viscosity 4.45 centipoise at 1,743°C surface tension 1,835-1,965 dynes/cm electrical resistivity 139 microhm-cm at the melting point. Magnetic properties attracted by magnets rapidly loses its magnetism ferromagnetic at ordinary temperature becomes paramagnetic when heated to its Curie point, 768°C. 

Figure 6.39(a) shows the vs. T curve, normalized to the RT value, for a 100 nm thick a-/ -NPNN/glass film obtained from electron paramagnetic resonance (EPR) measurements with the static magnetic field applied perpendicular to the substrate plane. As previously shown in Fig. 3.19, the molecular a -planes are parallel to the substrate s surface. The data points closely follow the Curie-Weiss law = (T — w)/C, where C stands for the Curie constant. In this case w — —0.3 K, indicating that the net intermolecular interactions are weakly anfiferromagnetic. No hint of a transition at low temperature is observed. These results coincide with those derived from SQUID measurements on a single a-p-NPNN crystal (Tamura etal, 2003), where 0.5 < w < 0, which are displayed in Fig. 6.40. 

Curie s concept [7], which considered that the normal growth rates of crystal faces are proportional to the surface free energies and... 

The precipitated metal is a grey-black powder, but when sublimed, polonium is silvery in thick layers [ 0.2 mg (1 curie)/cm2] and a transparent smoked film in thin ones. When the thicker metal mirrors, obtained by vacuum sublimation onto a glass surface, are treated with a little 8 N nitric acid, a part of the metal can be detached from the glass as a thin foil. 

Fig. II. (a) Temperature dependence of the magnetization for 200-nm thick Ga, MnrAs with x =0.053. The magnetic field is applied perpendicular to the sample surface (hard axis). The inset shows the temperature dependence of the remanent magnetization (0 T) and the magnetization at 1 T in a field parallel to the film surface, (b) Temperature dependence of the saturation magnetization determined from the data shown in (a) by using ArTott plots (closed circles). Open circles show inverse magnetic susceptibility and the Curie-Weiss fit is depicted by the solid straight line (Ohno and Matsukura 2001).

Thus, melting of a crystalline substance without superheating is a superficial effect. Pre-melting phenomena are apparently also related to the formation of liquid films on the surfaces of crystals, if not to other incidental causes (for example, impurities), and are not pertinent to Frenkel s theory. Heterophase fluctuations are quite large where the difference between two phases and the surface tension between them tend to zero—near the critical point and near the Curie point. The first case is commonly known, the second was earlier investigated quantitatively in Landau s fine work [13, 14]. 

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