01/03/2012

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Ekor 1). This will require applying an external anode current, part of which will go to suppress the cathodic reaction to a value of i , while the other part - to accelerate the reaction of metal ionization in. The rate of metal dissolution at this potential is. From Fig. Table 1 shows that although corrosion rate and decreased, but the overall rate of dissolution of the metal increased the amount. For these reasons, you can not use the imposition of the anode current for corrosion protection of actively dissolving metals. But Many metals, especially with incomplete d-electron layers, the displacement capacity of up to magnitude Ekor E 'pass into a passive state, which corresponds to a sharp deceleration of the ionization, to protect them used epoxy enamel EP. Current of metal dissolution is reduced to the value of icor ipas (Fig. 3). In this case the current solution of the metal decreases tenfold. External anodic current density, which is required for the transfer of the metal in passive state, is usually quite high. When the metal is turned into a passive state, its maintenance requires further applying an external current, small in size, which makes the anode protection highly effective method of preventing corrosion of metals. For example, to start the passivation of stainless steel in 66% solution of H2SO4 at room temperature ( 24?) Is required anode current density 6 A/m2, and to further promote passive state - only 10 - 3 A/m2. The currents of the anodic protection is usually much smaller than the corresponding current cathodic protection. It must be emphasized that anodic protection is suitable for corrosion control only easily passivated metals during anodic polarization (Fe, Ni, Cr, Mo, Ti, Zr) and does not apply to metals such as Zn, Cu, Cd, Ag.
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The Dead Sea The Dead Sea is located in the Negev desert that stretches to the south of Israel, and takes about 60% of its territory. Geographically, the Negev is located at an altitude of 600-800 meters above sea level and is divided into northern, - irrigated with large on Israeli standards cities: Ashkelon, Ashdod, Sderot, Netivot and Ofakim - which is the country's largest forest area and the local agricultural economy, and the south, with small towns - Oasis: Dimona and Arad. Coast The Dead Sea is the lowest portion of the Negev, as well as the lowest portion of land on the Earth: it is 420 meters below sea level. In fact - this is a salt lake, which consists of two basins, together reaching 72 km. in long and 18 km. in width. On the eastern shore of the Dead Sea are the main resort areas: Ein Bokek and Ein Gedi. The density of the Dead Sea is so great, that allows to lie on the surface without moving. The bottom strewn with small stalactites, and therefore we recommend wearing plastic shoes for swimming. Due to high salinity and air solar activity - in the summer are urged to limit their exposure to the open territory outside the hotel, so as not to burn the first day and do not spoil your holiday. The main method of treatment in the Dead Sea resorts - heliotherapy in conjunction with salt baths with water rich in bromide and other salts and minerals almost 25% solution. The average annual daytime temperatures in the Negev desert, rarely dropping below 40 C and high humidity (35-50%) contributes to the rapid and smooth tan. Rapa Dead Sea contains several dozen chemical elements different in composition from other salt lakes on the planet. The indications for treatment...