Iron oxide effect of citrate

Waite, T. D., and F. M. M. Morel (1984), "Photoreductive Dissolution of Colloidal Iron Oxide Effect of Citrate," J. Colloid Interface Sci. 102, 121-137. 

Waite, TD. Morel, E.M.M. (1984) Photoreduc-tive dissolution of colloidal iron oxide Effect of citrate. J. Colloid Interface Sci. 102 121-... 

Waite, T.D. and Morel, F.M.M., 1989a. Photoreductive dissolution of colloidal iron oxide effect of citrate. 3. Colloid Interface Sci., 102 121-137. 

Secondary antioxidants, i.e., sequestrants or chelators, are important compounds in the prevention of lipid oxidation. The effect of chelators tested varied with the different compounds. Of those chelators tested, ethylenediaminetetraacetic acid (EDTA, tetrasodium salt) and sodium phytate were the most effective inhibitors of lipid oxidation (so indicated by low hexanal and TEARS values) and MFD (as seen by high CBB and low PIT and CBD intensity values), see Table 5. Sodium phytate was previously shown to chelate iron and thus, was proposed as a food antioxidant(7J). Sodium citrate at a concentration of 500... 

Edmondson et al (1971), who studied the enrichment of whole milk with iron, found that ferrous compounds normally caused a definite oxidized flavor when added before pasteurization. Aeration before addition of the iron reduced the off-flavor. The authors recommended the addition of ferric ammonium citrate followed by pasteurization at 81 °C. Kurtz et al. (1973) reported that iron salts can be added in amounts equivalent to 20 mg iron per liter of skim milk with no adverse flavor effects when iron-fortified dry milk is reconstituted to skim milk or used in the preparation of 2% milk. Hegenauer et al. (1979A) reported that emulsification of milk fat prior to fortification greatly reduced lipid peroxidation by all metal complexes. These researchers (Hegenauer et al. 1979B) concluded that chelated iron and copper should be added after homogenization but before pasteurization by a high-temperature-short-time process. 

The objective of the present study is to examine the desorption kinetics of Cd following its adsorption on iron oxides. To simulate the effects of organic ligands in soil rhizosphere environment and chloride-bearing fertilizer, Cd desorption caused by citrate, acetate and chloride was investigated. 

However, this trend is not very clear in the citrate and acetate extractant systems. As indicated by the total C content in the iron oxide samples (Table 1), there was a significant amount of citrate coprecipitated with iron oxides formed at the initial cit-rate/Fe(II) MRs of 0.01 and 0.1. The coprecipitated citrate with iron oxides could have different effects on the Cd desorphon induced by inorganic and organic extractants, since the stability constants for the Cd- and Fe-ligand complexes vary greatly. 

ESCA analysis of ammonium citrate and HTTHG treated steel is currently being undertaken in an attempt to better understand the chemical processes which are occuring at the surface. The following proposal is presented in an attempt to explain the bond improvement mechanism. As stated earlier, the ammonium citrate pretreatraent was found to be a necessary component of the treatment. Citric acid is known to be an effective treatment for the removal of iron oxide from stainless steel... 

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