Enhancement passive

Other corrosion inhibitors also enhance passivity without electrochemical reduction, by depositing insoluble oxidation products into the passivating film. For example benzoate ions cause deposition of ferric benzoate into the oxide, but do not provide any cathodic reaction. 

The alloying elements molybdenum and copper do not, by themselves, enhance passivity of nickel in acid solutions, but instead ennoble the metal. This means that, in practice, these alloying elements confer benefit in precisely those circumstances where chromium does not, viz. hydrogen-evolving acidic solutions, by reducing the rate of anodic dissolution. In more oxidising media the anodic activity increases, and, since binary Ni-Mo and Ni-Cu alloys do not passivate in acidic solutions, they are generally unsuitable in such media. 

Niobium is resistant to pitting and general corrosion in hydrobromic acid up to the azeotropic concentration of 47wt% and 124°C the presence of free bromine enhances passivity . 

Table 19.S). In particular, they have established that the presence of dissolved O2 enhances passivity thus causing E, to become more positive, and consider that this explains the failure of France and Greene to obtain accord between controlled potential tests in hydrogen-saturated chloride solutions and immersion tests in oxygenated chloride solutions at the same potentials. 

NijenhuisT et al Enhanced passive Ca2+ reabsorption and reduced Mg2+ channel abundance explains thiazide-induced hypocalciuria and hypomagnesemia. 3 Clin Invest 2005 115 1651. [PMID 15902302]... 

Previous work on N2B titin-expressing myocardium has revealed that the N2B PEVK region and F-actin interact (Kulke et al, 2001 Yamasaki et al, 2001), enhancing passive stiffness. Evidence suggests that this interaction can be inhibited by SI 00, provided that calcium is present (Yamasaki et al., 2002). Whether the PEVK segment of N2BA titin also interacts with actin has not been studied. Considering the different composition of N2B... 

Enhancing -> passivation of iron and steel and dissolving refractory substances such as titanium slag, copper-yttrium oxide, and metal fluorides. 

Intestinal calcium absorption is influenced by dietary factors. Lactose and other sugars increase water absorption, thereby enhancing passive calcium uptake. The effect of lactose is especially valuable because of its presence in milk, a major source of calcium. Lactose also increases absorption of other metal ions. This effect may contribute to the incidence of lead poisoning (plumbism) among young inner-city children exposed to high dietary levels of both lead and lactose. 

The Advanced Pressurized Reactor AP-600 (Westinghouse) final design certification by NRC is expected for 1998. A larger unit of an advanced PWR, the System 80+, with 1300 MW(e) is being developed by ABB/Construction Eng. [86]. These designs with enhanced passive safety features are pursued in the USA to provide additional electricity and replace retired plants. 

Loo WW. (1994). Electrokinetic enhanced passive in situ bioremediation of soil and ground-water containing gasoline, diesel and kerosene. Paper presented at the HAZMACON Conference, March 29-31, San Jose, CA. 

The available processes can be broadly divided into four categories mechanical, chemical, electrochemical and others. All of these processes are designed to modify the aluminium alloy to provide a high energy, wettable surface that is relatively free from contamination. As mentioned, the most successful also provide additional surface roughness and enhanced passivation. 

Encouraged with this result, polarisation of WS was done in 0.1 M Na2S04 at pH 9.2 with a scan rate of 0.005 mV/sec. Passivity was obtained and with a current density of about 500 pm/cm and the range continued beyond -850 mV as shown in Fig. 4.5. Since it has been reported in the literature [23] that very small addition of Cl ions enhance passive range, the polarisation experiment of WS was repeated in 0.1 M Na2S04 + 0.001 M NaCl at pH 8.6 with 0.005 mV/sec scan rate. Passivity range was indeed found to be enhanced as indicated in Fig. 4.6. 

A pool is provided at the bottom section of the lower drywell for the purpose of collecting and confining fuel melt debris. The pool is permanently filled with water to enhance passive safety. 

It is an integrated PWR, completely immersed in a large pool of cold boronated on water which builds up on the density lock concept originally proposed by ABB ATOM for the PIUS plant and embodies revolutionary ideas for enhanced passive safety. The ISIS reactor components, on the other hand, are mainly based on proven technology derived from the ANSALDO experience in the field of both LWRs and LMFBRs. 

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